Composition of matter for use in organic light-emitting diodes

ABSTRACT

The present disclosure relates in parts to compounds capable of emitting delayed fluorescence and uses of these compounds in organic light-emitting diodes.

RELATED APPLICATIONS

This application claims the benefit of priority to U.S. ProvisionalPatent Application Ser. No. 62/523,948, filed Jun. 23, 2017; U.S.Provisional Patent Application Ser. No. 62/523,956, filed Jun. 23, 2017;U.S. Provisional Patent Application Ser. No. 62/524,049, filed Jun. 23,2017; and U.S. Provisional Patent Application Ser. No. 62/653,880, filedApr. 6, 2018.

BACKGROUND

An organic light-emitting diode (OLED) is a light-emitting diode (LED)in which a film of organic compounds is placed between two conductors,which film emits light in response to excitation, such as an electriccurrent. OLEDs are useful in displays, such as television screens,computer monitors, mobile phones, and tablets. A problem inherent inOLED displays is the limited lifetime of the organic compounds. OLEDsthat emit blue light, in particular, degrade at a significantlyincreased rate as compared to green or red OLEDs.

OLED materials rely on the radiative decay of molecular excited states(excitons) generated by recombination of electrons and holes in a hosttransport material. The nature of excitation results in interactionsbetween electrons and holes that split the excited states into brightsinglets (with a total spin of 0) and dark triplets (with a total spinof 1). Since the recombination of electrons and holes affords astatistical mixture of four spin states (one singlet and three tripletsublevels), conventional OLEDs have a maximum theoretical efficiency of25%.

To date, OLED material design has focused on harvesting the remainingenergy from the normally dark triplets. Recent work to create efficientphosphors, which emit light from the normally dark triplet state, haveresulted in green and red OLEDs. Other colors, such as blue, however,require higher energy excited states, which accelerate the degradationprocess of the OLED.

The fundamental limiting factor to the triplet-singlet transition rateis a value of the parameter |H_(fi)/Δ|², where H_(fi) is the couplingenergy due to hyperfine or spin-orbit interactions, and Δ is theenergetic splitting between singlet and triplet states. Traditionalphosphorescent OLEDs rely on the mixing of singlet and triplet statesdue to spin-orbital (SO) interaction, increasing H_(fi), and affording alowest emissive state shared between a heavy metal atom and an organicligand. This results in energy harvesting from all higher singlet andtriplet states, followed by phosphorescence (relatively short-livedemission from the excited triplet). The shortened triplet lifetimereduces triplet exciton annihilation by charges and other excitons.Recent work by others suggests that the limit to the performance ofphosphorescent materials has been reached.

SUMMARY

The present disclosure relates to novel materials for OLEDs. These OLEDscan reach higher excitation states without rapid degradation. It has nowbeen discovered that thermally activated delayed fluorescence (TADF),which relies on minimization of A as opposed to maximization of H_(fi),can transfer population between singlet levels and triplet sublevels ina relevant timescale, such as, for example, 1-100 μs. The compoundsdescribed herein are capable of luminescing at higher energy excitationstates than compounds previously described.

In one aspect, the present disclosure provides compounds of Formula (I):

wherein

A is independently selected from

X^(A) is independently selected from O, S, and NR^(A′);

R^(A) is independently selected from hydrogen, deuterium, halogen,cyano, substituted or unsubstituted alkyl, substituted or unsubstitutedalkoxy, substituted or unsubstituted aryl, substituted or unsubstitutedaryloxy, substituted or unsubstituted heteroaryl, substituted orunsubstituted heteroaryloxy, and silyl;

two or more instances of R^(A) taken together can form a ring system;

R^(A′) is independently selected from hydrogen, deuterium, substitutedor unsubstituted alkyl, substituted or unsubstituted aryl, andsubstituted or unsubstituted heteroaryl;

two or more instances of R^(A′) and R^(A) taken together can form a ringsystem;

D is independently selected from

X^(D) is independently selected from a bond, O, S, NR^(D′), C(O),substituted or unsubstituted methylene, substituted or unsubstitutedethylene, substituted or unsubstituted vinylene, substituted orunsubstituted o-arylene, and substituted or unsubstitutedo-heteroarylene; wherein each instance of methylene, ethylene, vinylene,o-arylene or o-heteroarylene can be substituted with one or moresubstituents independently selected from deuterium, substituted orunsubstituted alkyl, substituted or unsubstituted aryl, and substitutedor unsubstituted heteroaryl;

two or more instances of X^(D) taken together can form a ring system;

R^(D) is independently selected from hydrogen, deuterium, substituted orunsubstituted alkyl, substituted or unsubstituted alkoxy, substituted orunsubstituted amino, substituted or unsubstituted aryl, substituted orunsubstituted aryloxy, substituted or unsubstituted heteroaryl,substituted or unsubstituted heteroaryloxy, and silyl;

two or more instances of R^(D) taken together can form a ring system;

R^(D′) is independently selected from hydrogen, deuterium, substitutedor unsubstituted alkyl, substituted or unsubstituted amino, substitutedor unsubstituted aryl, and substituted or unsubstituted heteroaryl;

two or more instances of R^(D′) and R^(D) taken together can form a ringsystem;

L^(A) and L^(D) are independently selected from single bond, substitutedor unsubstituted arylene, and substituted or unsubstituted heteroarylenegroup; wherein each instance of arylene and heteroarylene can besubstituted with one or more substituents independently selected fromdeuterium, substituted or unsubstituted alkyl, substituted orunsubstituted aryl, and substituted or unsubstituted heteroaryl; two ormore of these substituents taken together can form a ring system;

Ar is independently selected from substituted or unsubstituted aryl andsubstituted or unsubstituted heteroaryl group, wherein the substitutedor unsubstituted heteroaryl group does not contain a ring nitrogen atom;each substituent is independently selected from deuterium, substitutedor unsubstituted alkyl, substituted or unsubstituted aryl, andsubstituted or unsubstituted heteroaryl; two or more of thesesubstituents taken together can form a ring system;

k is 1 or 2;

n is 1 to 4;

m is 0 to 3

(k+m+n) is 2 to 6; and

each “*” represents a point of attachment to Formula (I);

provided that if n is greater than or equal to 2, then L^(A) is not asingle bond.

In one aspect, the present disclosure provides compounds of Formula(II):

wherein

A is independently selected from

R₁, R₂, R₃, and R₄ are independently selected from D, H, and Ph;

D is independently selected from

at least one instance of D is present;

0 to 3 instances of H are present;

0 to 3 instances of Ph are present; and

if R₃ is D, then at least one of R₁, R₂, R₄ is not H; and

if R₂ is D and R₄ is D, then at least one of R₁ or R₃ is not H.

In one aspect, the present disclosure provides compounds of Formula(III):

wherein

A is independently selected from

X¹, X₂, X₃, and X₄ are independently selected from H, deuterium, and D;

D is independently selected from

Z₁ is selected from C(CH₃)₂, C(Ph)₂, O, and N(Ph); and

Z₂ is independently selected from alkyl, aryl, and heteroaryl, and ispreferably selected from methyl, tert-butyl, phenyl, carbazolyl,phenylcarbazolyl, diphenylamino, and triphenylamino.

In one aspect, the present disclosure provides compounds of Formula(IV):

wherein

X is C(R₆);

R₁, R₂, R₃, R₄, R₅, and R₆ are independently selected from the groupconsisting of A, D, H, deuterium, and Ph;

at least two of R₁, R₂, R₃, R₄, R₅, and R₆ is A;

at least one of R₁, R₂, R₃, R₄, R₅, and R₆ is D;

A is

D is

Y is C(H) or N;

at least one instance of Y is N; and

Z is H, Me, or Ph.

In another aspect, the present disclosure provides use of the compoundsin a device. In some embodiments, provided herein is an organiclight-emitting diode (OLED) comprising an anode, a cathode, and at leastone organic layer comprising a light-emitting layer between the anodeand the cathode, wherein the light-emitting layer comprises:

a host material; and

a compound of Formula (I), (II), (III), or (IV);

wherein the compound of formula (I), (II), (III), or (IV) is alight-emitting material.

In some embodiments, a compound of Formula (I), (II), (III), or (IV) isused in a screen or a display.

In yet another aspect, the present disclosure relates to a method ofmanufacturing an OLED display, the method comprising:

forming a barrier layer on a base substrate of a mother panel;

forming a plurality of display units in units of cell panels on thebarrier layer;

forming an encapsulation layer on each of the display units of the cellpanels; and

applying an organic film to an interface portion between the cellpanels.

BRIEF DESCRIPTION OF THE DRAWING

The FIGURE is a schematic wherein 1 denotes a substrate, 2 denotes ananode, 3 denotes a hole injection layer, 4 denotes a hole transportinglayer, 5 denotes a light-emitting layer, 6 denotes an electrontransporting layer, and 7 denotes a cathode.

DETAILED DESCRIPTION

In one aspect, the present disclosure provides compounds of Formula (I).

In some embodiments, the compounds have a structure of Formula (I):

wherein

-   -   A is independently selected from

X^(A) is independently selected from O, S, and NR^(A′);

R^(A) is independently selected from hydrogen, deuterium, halogen,cyano, substituted or unsubstituted alkyl, substituted or unsubstitutedalkoxy, substituted or unsubstituted aryl, substituted or unsubstitutedaryloxy, substituted or unsubstituted heteroaryl, substituted orunsubstituted heteroaryloxy, and silyl;

two or more instances of R^(A) taken together can form a ring system;

R^(A′) is independently selected from hydrogen, deuterium, substitutedor unsubstituted alkyl, substituted or unsubstituted aryl, andsubstituted or unsubstituted heteroaryl;

two or more instances of R^(A′) and R^(A) taken together can form a ringsystem;

D is independently selected from

X° is independently selected from a bond, O, S, NR^(D′), C(O),substituted or unsubstituted methylene, substituted or unsubstitutedethylene, substituted or unsubstituted vinylene, substituted orunsubstituted o-arylene, and substituted or unsubstitutedo-heteroarylene; wherein each instance of methylene, ethylene, vinylene,o-arylene or o-heteroarylene can be substituted with one or moresubstituents independently selected from deuterium, substituted orunsubstituted alkyl, substituted or unsubstituted aryl, and substitutedor unsubstituted heteroaryl;

two or more instances of X^(D) taken together can form a ring system;

R^(D) is independently selected from hydrogen, deuterium, substituted orunsubstituted alkyl, substituted or unsubstituted alkoxy, substituted orunsubstituted amino, substituted or unsubstituted aryl, substituted orunsubstituted aryloxy, substituted or unsubstituted heteroaryl,substituted or unsubstituted heteroaryloxy, and silyl;

two or more instances of R^(D) taken together can form a ring system;

R^(D′) is independently selected from hydrogen, deuterium, substitutedor unsubstituted alkyl, substituted or unsubstituted amino, substitutedor unsubstituted aryl, and substituted or unsubstituted heteroaryl;

two or more instances of R^(D′) and R^(D) taken together can form a ringsystem;

L^(A) and L^(D) are independently selected from single bond, substitutedor unsubstituted arylene, and substituted or unsubstituted heteroarylenegroup; wherein each instance of arylene and heteroarylene can besubstituted with one or more substituents independently selected fromdeuterium, substituted or unsubstituted alkyl, substituted orunsubstituted aryl, and substituted or unsubstituted heteroaryl; two ormore of these substituents taken together can form a ring system;

Ar is independently selected from substituted or unsubstituted aryl andsubstituted or unsubstituted heteroaryl group, wherein the substitutedor unsubstituted heteroaryl group does not contain a ring nitrogen atom;each substituent is independently selected from deuterium, substitutedor unsubstituted alkyl, substituted or unsubstituted aryl, andsubstituted or unsubstituted heteroaryl; two or more of thesesubstituents taken together can form a ring system;

k is 1 or 2;

n is 1 to 4;

m is 0 to 3

(k+m+n) is 2 to 6; and

each “*” represents a point of attachment to Formula (I);

provided that if n is greater than or equal to 2, then L^(A) is not asingle bond.

In one aspect, the present disclosure provides compounds of Formula(II):

wherein

A is independently selected from

R₁, R₂, R₃, and R₄ are independently selected from D, H, and Ph;

D is independently selected from

at least one instance of D is present;

0 to 3 instances of H are present;

0 to 3 instances of Ph are present; and

if R₃ is D, then at least one of R₁, R₂, R₄ is not H; and

if R₂ is D and R₄ is D, then at least one of R₁ or R₃ is not H.

In one aspect, the present disclosure provides compounds of Formula(III):

wherein

A is independently selected from

X₁, X₂, X₃, and X₄ are independently selected from H deuterium, and D;

D is independently selected from

Z₁ is selected from C(CH₃)₂, C(Ph)₂, O, and N(Ph); and

Z₂ is independently selected from alkyl, aryl, and heteroaryl, and ispreferably selected from methyl, tert-butyl, phenyl, carbazolyl,phenylcarbazolyl, diphenylamino, and triphenylamino.

In one aspect, the present disclosure provides compounds of Formula(IV):

wherein

X is C(R₆);

R₁, R₂, R₃, R₄, R₅, and R₆ are independently selected from the groupconsisting of A, D, H, deuterium, and Ph;

at least two of R₁, R₂, R₃, R₄, R₅, and R₆ is A;

at least one of R₁, R₂, R₃, R₄, R₅, and R₆ is D;

A is

D is

Y is C(H) or N;

at least one of Y is N;

Z is H, Me, or Ph

The examples are provided by way of explanation of the disclosure, andnot by way of limitation of the disclosure. In fact, it will be apparentto those skilled in the art that various modification and variations canbe made in the present disclosure without departing from the scope orspirit of the disclosure. For instance, features illustrated ordescribed as part of one embodiment can be used on another embodiment toyield a still further embodiment. Thus it is intended that the presentdisclosure cover such modifications and variations as come within thescope of the appended claims and their equivalents. Other objects,features, and aspects of the present disclosure are disclosed in, or canbe derived from, the following detailed description. It is to beunderstood by one of ordinary skill in the art that the presentdiscussion is a description of exemplary embodiments only, and is not tobe construed as limiting the broader aspects of the present disclosure.

Definitions

Unless otherwise defined herein, scientific and technical terms used inthis application shall have the meanings that are commonly understood bythose of ordinary skill in the art. Generally, nomenclature used inconnection with, and techniques of, chemistry described herein, arethose well-known and commonly used in the art.

The term “acyl” is art-recognized and refers to a group represented bythe general formula hydrocarbylC(O)—, preferably alkylC(O)—.

The term “acylamino” is art-recognized and refers to an amino groupsubstituted with an acyl group and may be represented, for example, bythe formula hydrocarbylC(O)NH—.

The term “acyloxy” is art-recognized and refers to a group representedby the general formula hydrocarbylC(O)O—, preferably alkylC(O)O—.

The term “alkoxy” refers to an alkyl group, having an oxygen attachedthereto. Representative alkoxy groups include methoxy, trifluoromethoxy,ethoxy, propoxy, tert-butoxy and the like.

The term “alkoxyalkyl” refers to an alkyl group substituted with analkoxy group and may be represented by the general formulaalkyl-O-alkyl.

The term “alkenyl”, as used herein, refers to an aliphatic groupcomprising at least one double bond and is intended to include both“unsubstituted alkenyls” and “substituted alkenyls”, the latter of whichrefers to alkenyl moieties having substituents replacing a hydrogen onone or more carbons of the alkenyl group. Typically, a straight chainedor branched alkenyl group has from 1 to about 20 carbon atoms,preferably from 1 to about 10 unless otherwise defined. Suchsubstituents may occur on one or more carbons that are included or notincluded in one or more double bonds. Moreover, such substituentsinclude all those contemplated for alkyl groups, as discussed below,except where stability is prohibitive. For example, substitution ofalkenyl groups by one or more alkyl, carbocyclyl, aryl, heterocyclyl, orheteroaryl groups is contemplated.

An “alkyl” group or “alkane” is a straight chained or branchednon-aromatic hydrocarbon which is completely saturated. Typically, astraight chained or branched alkyl group has from 1 to about 20 carbonatoms, preferably from 1 to about 10 unless otherwise defined. In someembodiments, the alkyl group has from 1 to 8 carbon atoms, from 1 to 6carbon atoms, from 1 to 4 carbon atoms, or from 1 to 3 carbon atoms.Examples of straight chained and branched alkyl groups include methyl,ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl, tert-butyl, pentyl,hexyl, pentyl and octyl.

Moreover, the term “alkyl” as used throughout the specification,examples, and claims is intended to include both “unsubstituted alkyls”and “substituted alkyls”, the latter of which refers to alkyl moietieshaving substituents replacing a hydrogen on one or more substitutablecarbons of the hydrocarbon backbone. Such substituents, if not otherwisespecified, can include, for example, a halogen (e.g., fluoro), ahydroxyl, a carbonyl (such as a carboxyl, an alkoxycarbonyl, a formyl,or an acyl), a thiocarbonyl (such as a thioester, a thioacetate, or athioformate), an alkoxy, a phosphoryl, a phosphate, a phosphonate, aphosphinate, an amino, an amido, an amidine, an imine, a cyano, a nitro,an azido, a sulfhydryl, an alkylthio, a sulfate, a sulfonate, asulfamoyl, a sulfonamido, a sulfonyl, a heterocyclyl, an aralkyl, or anaromatic or heteroaromatic moiety. In preferred embodiments, thesubstituents on substituted alkyls are selected from C₁₋₆ alkyl, C₃₋₆cycloalkyl, halogen, carbonyl, cyano, or hydroxyl. In more preferredembodiments, the substituents on substituted alkyls are selected fromfluoro, carbonyl, cyano, or hydroxyl. It will be understood by thoseskilled in the art that the moieties substituted on the hydrocarbonchain can themselves be substituted, if appropriate. For instance, thesubstituents of a substituted alkyl may include substituted andunsubstituted forms of amino, azido, imino, amido, phosphoryl (includingphosphonate and phosphinate), sulfonyl (including sulfate, sulfonamido,sulfamoyl and sulfonate), and silyl groups, as well as ethers,alkylthios, carbonyls (including ketones, aldehydes, carboxylates, andesters), —CF₃, —CN and the like. Exemplary substituted alkyls aredescribed below. Cycloalkyls can be further substituted with alkyls,alkenyls, alkoxys, alkylthios, aminoalkyls, carbonyl-substituted alkyls,—CF₃, —CN, and the like.

The term “C_(x-y)” when used in conjunction with a chemical moiety, suchas, acyl, acyloxy, alkyl, alkenyl, alkynyl, or alkoxy is meant toinclude groups that contain from x to y carbons in the chain. Forexample, the term “C_(x-y) alkyl” refers to substituted or unsubstitutedsaturated hydrocarbon groups, including straight-chain alkyl andbranched-chain alkyl groups that contain from x to y carbons in thechain, including haloalkyl groups. Preferred haloalkyl groups includetrifluoromethyl, difluoromethyl, 2,2,2-trifluoroethyl, andpentafluoroethyl. C₀ alkyl indicates a hydrogen where the group is in aterminal position, a bond if internal. The terms “C₂₋₄ alkenyl” and“C_(2-y) alkynyl” refer to substituted or unsubstituted unsaturatedaliphatic groups analogous in length and possible substitution to thealkyls described above, but that contain at least one double or triplebond respectively.

The term “alkylamino”, as used herein, refers to an amino groupsubstituted with at least one alkyl group.

The term “alkylthio”, as used herein, refers to a thiol groupsubstituted with an alkyl group and may be represented by the generalformula alkylS—.

The term “arylthio”, as used herein, refers to a thiol group substitutedwith an alkyl group and may be represented by the general formulaarylS—.

The term “alkynyl”, as used herein, refers to an aliphatic groupcomprising at least one triple bond and is intended to include both“unsubstituted alkynyls” and “substituted alkynyls”, the latter of whichrefers to alkynyl moieties having substituents replacing a hydrogen onone or more carbons of the alkynyl group. Typically, a straight chainedor branched alkynyl group has from 1 to about 20 carbon atoms,preferably from 1 to about 10 unless otherwise defined. Suchsubstituents may occur on one or more carbons that are included or notincluded in one or more triple bonds. Moreover, such substituentsinclude all those contemplated for alkyl groups, as discussed above,except where stability is prohibitive. For example, substitution ofalkynyl groups by one or more alkyl, carbocyclyl, aryl, heterocyclyl, orheteroaryl groups is contemplated.

The term “amide”, as used herein, refers to a group

wherein each R^(A) independently represent a hydrogen or hydrocarbylgroup, or two R^(A) are taken together with the N atom to which they areattached complete a heterocycle having from 4 to 8 atoms in the ringstructure.

The terms “amine” and “amino” are art-recognized and refer to bothunsubstituted and substituted amines and salts thereof, e.g., a moietythat can be represented by

wherein each R^(A) independently represents a hydrogen or a hydrocarbylgroup, or two R^(A) are taken together with the N atom to which they areattached complete a heterocycle having from 4 to 8 atoms in the ringstructure.

The term “aminoalkyl”, as used herein, refers to an alkyl groupsubstituted with an amino group.

The term “aralkyl”, as used herein, refers to an alkyl group substitutedwith an aryl group.

The term “aryl” as used herein include substituted or unsubstitutedsingle-ring aromatic groups in which each atom of the ring is carbon.Preferably the ring is a 6- or 20-membered ring, more preferably a6-membered ring. The term “aryl” also includes polycyclic ring systemshaving two or more cyclic rings in which two or more carbons are commonto two adjoining rings wherein at least one of the rings is aromatic,e.g., the other cyclic rings can be cycloalkyls, cycloalkenyls,cycloalkynyls, aryls, heteroaryls, and/or heterocyclyls. Aryl groupsinclude benzene, naphthalene, phenanthrene, phenol, aniline, and thelike.

The term “carbamate” is art-recognized and refers to a group

wherein each R^(A) independently represent hydrogen or a hydrocarbylgroup, such as an alkyl group, or both R^(A) taken together with theintervening atom(s) complete a heterocycle having from 4 to 8 atoms inthe ring structure.

The terms “carbocycle”, and “carbocyclic”, as used herein, refers to asaturated or unsaturated ring in which each atom of the ring is carbon.Preferably, a carbocylic group has from 3 to 20 carbon atoms. The termcarbocycle includes both aromatic carbocycles and non-aromaticcarbocycles. Non-aromatic carbocycles include both cycloalkane rings, inwhich all carbon atoms are saturated, and cycloalkene rings, whichcontain at least one double bond. “Carbocycle” includes 5-7 memberedmonocyclic and 8-12 membered bicyclic rings. Each ring of a bicycliccarbocycle may be selected from saturated, unsaturated and aromaticrings. Carbocycle includes bicyclic molecules in which one, two or threeor more atoms are shared between the two rings. The term “fusedcarbocycle” refers to a bicyclic carbocycle in which each of the ringsshares two adjacent atoms with the other ring. Each ring of a fusedcarbocycle may be selected from saturated, unsaturated and aromaticrings. In an exemplary embodiment, an aromatic ring, e.g., phenyl (Ph),may be fused to a saturated or unsaturated ring, e.g., cyclohexane,cyclopentane, or cyclohexene. Any combination of saturated, unsaturatedand aromatic bicyclic rings, as valence permits, is included in thedefinition of carbocyclic. Exemplary “carbocycles” include cyclopentane,cyclohexane, bicyclo[2.2.1]heptane, 1,5-cyclooctadiene,1,2,3,4-tetrahydronaphthalene, bicyclo[4.2.0]oct-3-ene, naphthalene andadamantane. Exemplary fused carbocycles include decalin, naphthalene,1,2,3,4-tetrahydronaphthalene, bicyclo[4.2.0]octane,4,5,6,7-tetrahydro-1H-indene and bicyclo[4.1.0]hept-3-ene. “Carbocycles”may be substituted at any one or more positions capable of bearing ahydrogen atom.

A “cycloalkyl” group is a cyclic hydrocarbon which is completelysaturated. “Cycloalkyl” includes monocyclic and bicyclic rings.Preferably, a cycloalkyl group has from 3 to 20 carbon atoms. Typically,a monocyclic cycloalkyl group has from 3 to about 10 carbon atoms, moretypically 3 to 8 carbon atoms unless otherwise defined. The second ringof a bicyclic cycloalkyl may be selected from saturated, unsaturated andaromatic rings. Cycloalkyl includes bicyclic molecules in which one, twoor three or more atoms are shared between the two rings. The term “fusedcycloalkyl” refers to a bicyclic cycloalkyl in which each of the ringsshares two adjacent atoms with the other ring. The second ring of afused bicyclic cycloalkyl may be selected from saturated, unsaturatedand aromatic rings. A “cycloalkenyl” group is a cyclic hydrocarboncomprising one or more double bonds.

The term “carbocyclylalkyl”, as used herein, refers to an alkyl groupsubstituted with a carbocycle group.

The term “carbonate”, as used herein, refers to a group —OCO₂—R^(A),wherein R^(A) represents a hydrocarbyl group.

The term “carboxy”, as used herein, refers to a group represented by theformula —CO₂H.

The term “ester”, as used herein, refers to a group —C(O)OR^(A) whereinR^(A) represents a hydrocarbyl group.

The term “ether”, as used herein, refers to a hydrocarbyl group linkedthrough an oxygen to another hydrocarbyl group. Accordingly, an ethersubstituent of a hydrocarbyl group may be hydrocarbyl-O—. Ethers may beeither symmetrical or unsymmetrical.

Examples of ethers include, but are not limited to,heterocycle-O-heterocycle and aryl-O-heterocycle. Ethers include“alkoxyalkyl” groups, which may be represented by the general formulaalkyl-O-alkyl.

The terms “halo” and “halogen” as used herein means halogen and includeschloro, fluoro, bromo, and iodo.

The terms “heteroalkyl” and “heteroaralkyl”, as used herein, refers toan alkyl group substituted with a hetaryl group.

The term “heteroalkyl”, as used herein, refers to a saturated orunsaturated chain of carbon atoms and at least one heteroatom, whereinno two heteroatoms are adjacent.

The terms “heteroaryl” and “hetaryl” include substituted orunsubstituted aromatic single ring structures, preferably 5- to20-membered rings, more preferably 5- to 6-membered rings, whose ringstructures include at least one heteroatom, preferably one to fourheteroatoms, more preferably one or two heteroatoms. The terms“heteroaryl” and “hetaryl” also include polycyclic ring systems havingtwo or more cyclic rings in which two or more carbons are common to twoadjoining rings wherein at least one of the rings is heteroaromatic,e.g., the other cyclic rings can be cycloalkyls, cycloalkenyls,cycloalkynyls, aryls, heteroaryls, and/or heterocyclyls. Heteroarylgroups include, for example, pyrrole, furan, thiophene, imidazole,oxazole, thiazole, pyrazole, pyridine, pyrazine, pyridazine, pyrimidine,and carbazole, and the like.

The term “heteroatom” as used herein means an atom of any element otherthan carbon or hydrogen. Preferred heteroatoms are nitrogen, oxygen, andsulfur.

The terms “heterocyclyl”, “heterocycle”, and “heterocyclic” refer tosubstituted or unsubstituted non-aromatic ring structures, preferably 3-to 20-membered rings, more preferably 3- to 7-membered rings, whose ringstructures include at least one heteroatom, preferably one to fourheteroatoms, more preferably one or two heteroatoms. The terms“heterocyclyl” and “heterocyclic” also include polycyclic ring systemshaving two or more cyclic rings in which two or more carbons are commonto two adjoining rings wherein at least one of the rings isheterocyclic, e.g., the other cyclic rings can be cycloalkyls,cycloalkenyls, cycloalkynyls, aryls, heteroaryls, and/or heterocyclyls.Heterocyclyl groups include, for example, piperidine, piperazine,pyrrolidine, morpholine, lactones, lactams, and the like.

The term “heterocyclylalkyl”, as used herein, refers to an alkyl groupsubstituted with a heterocycle group.

The term “hydrocarbyl”, as used herein, refers to a group that is bondedthrough a carbon atom, wherein that carbon atom does not have a ═O or ═Ssubstituent. Hydrocarbyls may optionally include heteroatoms.Hydrocarbyl groups include, but are not limited to, alkyl, alkenyl,alkynyl, alkoxyalkyl, aminoalkyl, aralkyl, aryl, aralkyl, carbocyclyl,cycloalkyl, carbocyclylalkyl, heteroaralkyl, heteroaryl groups bondedthrough a carbon atom, heterocyclyl groups bonded through a carbon atom,heterocyclylalkyl, or hydroxyalkyl. Thus, groups like methyl,ethoxyethyl, 2-pyridyl, and trifluoromethyl are hydrocarbyl groups, butsubstituents such as acetyl (which has a ═O substituent on the linkingcarbon) and ethoxy (which is linked through oxygen, not carbon) are not.

The term “hydroxyalkyl”, as used herein, refers to an alkyl groupsubstituted with a hydroxy group.

The term “lower” when used in conjunction with a chemical moiety, suchas, acyl, acyloxy, alkyl, alkenyl, alkynyl, or alkoxy is meant toinclude groups where there are six or fewer non-hydrogen atoms in thesubstituent. A “lower alkyl”, for example, refers to an alkyl group thatcontains six or fewer carbon atoms. In some embodiments, the alkyl grouphas from 1 to 6 carbon atoms, from 1 to 4 carbon atoms, or from 1 to 3carbon atoms. In certain embodiments, acyl, acyloxy, alkyl, alkenyl,alkynyl, or alkoxy substituents defined herein are respectively loweracyl, lower acyloxy, lower alkyl, lower alkenyl, lower alkynyl, or loweralkoxy, whether they appear alone or in combination with othersubstituents, such as in the recitations hydroxyalkyl and aralkyl (inwhich case, for example, the atoms within the aryl group are not countedwhen counting the carbon atoms in the alkyl substituent).

The terms “polycyclyl”, “polycycle”, and “polycyclic” refer to two ormore rings (e.g., cycloalkyls, cycloalkenyls, cycloalkynyls, aryls,heteroaryls, and/or heterocyclyls) in which two or more atoms are commonto two adjoining rings, e.g., the rings are “fused rings”. Each of therings of the polycycle can be substituted or unsubstituted. In certainembodiments, each ring of the polycycle contains from 3 to 10 atoms inthe ring, preferably from 5 to 7.

In the phrase “poly(meta-phenylene oxides)”, the term “phenylene” refersinclusively to 6-membered aryl or 6-membered heteroaryl moieties.Exemplary poly(meta-phenylene oxides) are described in the first throughtwentieth aspects of the present disclosure.

The term “silyl” refers to a silicon moiety with three hydrocarbylmoieties attached thereto.

The term “substituted” refers to moieties having substituents replacinga hydrogen on one or more carbons of the backbone. It will be understoodthat “substitution” or “substituted with” includes the implicit provisothat such substitution is in accordance with permitted valence of thesubstituted atom and the substituent, and that the substitution resultsin a stable compound, e.g., which does not spontaneously undergotransformation such as by rearrangement, cyclization, elimination, etc.Moieties that may be substituted can include any appropriatesubstituents described herein, for example, acyl, acylamino, acyloxy,alkoxy, alkoxyalkyl, alkenyl, alkyl, alkylamino, alkylthio, arylthio,alkynyl, amide, amino, aminoalkyl, aralkyl, carbamate, carbocyclyl,cycloalkyl, carbocyclylalkyl, carbonate, ester, ether, heteroaralkyl,heterocyclyl, heterocyclylalkyl, hydrocarbyl, silyl, sulfone, orthioether. As used herein, the term “substituted” is contemplated toinclude all permissible substituents of organic compounds. In a broadaspect, the permissible substituents include acyclic and cyclic,branched and unbranched, carbocyclic and heterocyclic, aromatic andnon-aromatic substituents of organic compounds. The permissiblesubstituents can be one or more and the same or different forappropriate organic compounds. For purposes of this invention, theheteroatoms such as nitrogen may have hydrogen substituents and/or anypermissible substituents of organic compounds described herein whichsatisfy the valences of the heteroatoms. Substituents can include anysubstituents described herein, for example, a halogen, a hydroxyl, acarbonyl (such as a carboxyl, an alkoxycarbonyl, a formyl, or an acyl),a thiocarbonyl (such as a thioester, a thioacetate, or a thioformate),an alkoxy, a phosphoryl, a phosphate, a phosphonate, a phosphinate, anamino, an amido, an amidine, an imine, a cyano, a nitro, an azido, asulfhydryl, an alkylthio, a sulfate, a sulfonate, a sulfamoyl, asulfonamido, a sulfonyl, a heterocyclyl, an aralkyl, or an aromatic orheteroaromatic moiety. In preferred embodiments, the substituents onsubstituted alkyls are selected from C₁₋₆ alkyl, C₃₋₆ cycloalkyl,halogen, carbonyl, cyano, or hydroxyl. In more preferred embodiments,the substituents on substituted alkyls are selected from fluoro,carbonyl, cyano, or hydroxyl. It will be understood by those skilled inthe art that substituents can themselves be substituted, if appropriate.Unless specifically stated as “unsubstituted,” references to chemicalmoieties herein are understood to include substituted variants. Forexample, reference to an “aryl” group or moiety implicitly includes bothsubstituted and unsubstituted variants.

The term “sulfonate” is art-recognized and refers to the group SO₃H, ora pharmaceutically acceptable salt thereof.

The term “sulfone” is art-recognized and refers to the group—S(O)₂—R^(A), wherein R^(A) represents a hydrocarbyl.

The term “thioether”, as used herein, is equivalent to an ether, whereinthe oxygen is replaced with a sulfur.

The term “symmetrical molecule,” as used herein, refers to moleculesthat are group symmetric or synthetic symmetric. The term “groupsymmetric,” as used herein, refers to molecules that have symmetryaccording to the group theory of molecular symmetry. The term “syntheticsymmetric,” as used herein, refers to molecules that are selected suchthat no regioselective synthetic strategy is required.

The term “donor,” as used herein, refers to a molecular fragment thatcan be used in organic light-emitting diodes and is likely to donateelectrons from its highest occupied molecular orbital to an acceptorupon excitation. In an example embodiment, donors have an ionizationpotential greater than or equal to −6.5 eV.

The term “acceptor,” as used herein, refers to a molecular fragment thatcan be used in organic light-emitting diodes and is likely to acceptelectrons into its lowest unoccupied molecular orbital from a donor thathas been subject to excitation. In an example embodiment, acceptors havean electron affinity less than or equal to −0.5 eV.

The term “bridge,” as used herein, refers to a molecular fragment thatcan be included in a molecule which is covalently linked betweenacceptor and donor moieties. The bridge can, for example, be furtherconjugated to the acceptor moiety, the donor moiety, or both. Withoutbeing bound to any particular theory, it is believed that the bridgemoiety can sterically restrict the acceptor and donor moieties into aspecific configuration, thereby preventing the overlap between theconjugated n system of donor and acceptor moieties. Examples of suitablebridge moieties include phenyl, ethenyl, and ethynyl.

The term “multivalent,” as used herein, refers to a molecular fragmentthat is connected to at least two other molecular fragments. Forexample, a bridge moiety, is multivalent.

as used herein, refers to a point of attachment between two atoms.

“Hole transport layer (HTL)” and like terms mean a layer made from amaterial which transports holes. High hole mobility is recommended. TheHTL is used to help block passage of electrons transported by theemitting layer. Low electron affinity is typically required to blockelectrons. The HTL should desirably have larger triplets to blockexciton migrations from an adjacent emisse layer (EML). Examples of HTLcompounds include, but are not limited to,di(p-tolyl)aminophenyl]cyclohexane (TAPC),N,N-diphenyl-N,N-bis(3-methylphenyl)-1,1-biphenyl-4,4-diamine (TPD), andN,N′-diphenyl-N,N′-bis(1-naphthyl)-(1,1′-biphenyl)-4,4′-diamine. (NPB,α-NPD).

“Emitting layer” and like terms mean a layer which consists of host anddopant. The host material could be bipolar or unipolar, and may be usedalone or by combination of two or more host materials. Theopto-electrical properties of the host material may differ to which typeof dopant (Phosphorescent or Fluorescent) is used. For Fluorescentdopants, the assisting host materials should have good spectral overlapbetween adsorption of the dopant and emission of the host to induce goodFörster transfer to dopants. For Phosphorescent dopants, the assistinghost materials should have high triplet energy to confine triplets ofthe dopant.

“Dopant” and like terms, refer to an electron acceptor or a donator thatincreases the conductivity of an organic layer of an organic electronicdevice, when added to the organic layer as an additive. Organicsemiconductors may likewise be influenced, with regard to theirelectrical conductivity, by doping. Such organic semiconducting matrixmaterials may be made up either of compounds with electron-donorproperties or of compounds with electron-acceptor properties.

In the compounds of this invention any atom not specifically designatedas a particular isotope is meant to represent any stable isotope of thatatom. Unless otherwise stated, when a position is designatedspecifically as “H” or “hydrogen”, the position is understood to havehydrogen at its natural abundance isotopic composition. Also unlessotherwise stated, when a position is designated specifically as “D” or“deuterium”, the position is understood to have deuterium at anabundance that is at least 3340 times greater than the natural abundanceof deuterium, which is 0.015% (i.e., at least 50.1% incorporation ofdeuterium).

The term “isotopic enrichment factor” as used herein means the ratiobetween the isotopic abundance and the natural abundance of a specifiedisotope.

In various embodiments, compounds of this invention have an isotopicenrichment factor for each designated deuterium atom of at least 3500(52.5% deuterium incorporation at each designated deuterium atom), atleast 4000 (60% deuterium incorporation), at least 4500 (67.5% deuteriumincorporation), at least 5000 (75% deuterium), at least 5500 (82.5%deuterium incorporation), at least 6000 (90% deuterium incorporation),at least 6333.3 (95% deuterium incorporation), at least 6466.7 (97%deuterium incorporation), at least 6600 (99% deuterium incorporation),or at least 6633.3 (99.5% deuterium incorporation).

The term “isotopologue” refers to a species that differs from a specificcompound of this invention only in the isotopic composition thereof.

The term “compound,” when referring to a compound of this invention,refers to a collection of molecules having an identical chemicalstructure, except that there may be isotopic variation among theconstituent atoms of the molecules. Thus, it will be clear to those ofskill in the art that a compound represented by a particular chemicalstructure containing indicated deuterium atoms, will also contain lesseramounts of isotopologues having hydrogen atoms at one or more of thedesignated deuterium positions in that structure. The relative amount ofsuch isotopologues in a compound of this invention will depend upon anumber of factors including the isotopic purity of deuterated reagentsused to make the compound and the efficiency of incorporation ofdeuterium in the various synthesis steps used to prepare the compound.However, as set forth above the relative amount of such isotopologues intoto will be less than 49.9% of the compound. In other embodiments, therelative amount of such isotopologues in toto will be less than 47.5%,less than 40%, less than 32.5%, less than 25%, less than 17.5%, lessthan 10%, less than 5%, less than 3%, less than 1%, or less than 0.5% ofthe compound.

“Substituted with deuterium” refers to the replacement of one or morehydrogen atoms with a corresponding number of deuterium atoms.

Principles of OLED

OLEDs are typically composed of a layer of organic materials orcompounds between two electrodes, an anode and a cathode. The organicmolecules are electrically conductive as a result of delocalization of πelectronics caused by conjugation over part or all of the molecule. Whenvoltage is applied, electrons from the highest occupied molecularorbital (HOMO) present at the anode flow into the lowest unoccupiedmolecular orbital (LUMO) of the organic molecules present at thecathode. Removal of electrons from the HOMO is also referred to asinserting electron holes into the HOMO. Electrostatic forces bring theelectrons and the holes towards each other until they recombine and forman exciton (which is the bound state of the electron and the hole). Asthe excited state decays and the energy levels of the electrons relax,radiation having a frequency in the visible spectrum is emitted. Thefrequency of this radiation depends on the band gap of the material,which is the difference in energy between the HOMO and the LUMO.

As electrons and holes are fermions with half integer spin, an excitonmay either be in a singlet state or a triplet state depending on how thespins of the electron and hole have been combined, Statistically, threetriplet excitons will be formed for each singlet exciton. Decay fromtriplet states is spin forbidden, which results in increases in thetimescale of the transition and limits the internal efficiency offluorescent devices. Phosphorescent organic light-emitting diodes makeuse of spin-orbit interactions to facilitate intersystem crossingbetween singlet and triplet states, thus obtaining emission from bothsinglet and triplet states and improving the internal efficiency.

One prototypical phosphorescent material is iridiumtris(2-phenylpyridine) (Ir(ppy)₃) in which the excited state is a chargetransfer from the Ir atom to the organic ligand. Such approaches havereduced the triplet lifetime to about several μs, several orders ofmagnitude slower than the radiative lifetimes of fully-allowedtransitions such as fluorescence. Ir-based phosphors have proven to beacceptable for many display applications, but losses due to largetriplet densities still prevent the application of OLEDs to solid-statelighting at higher brightness.

Thermally activated delayed fluorescence (TADF) seeks to minimizeenergetic splitting between singlet and triplet states (Δ, ΔE_(ST)). Thereduction in exchange splitting from typical values of 0.4-0.7 eV to agap of the order of the thermal energy (proportional to kBT, where kBrepresents the Boltzmann constant, and T represents temperature) meansthat thermal agitation can transfer population between singlet levelsand triplet sublevels in a relevant timescale even if the couplingbetween states is small.

TADF molecules consist of donor and acceptor moieties connected directlyby a covalent bond or via a conjugated linker (or “bridge”). A “donor”moiety is likely to transfer electrons from its HOMO upon excitation tothe “acceptor” moiety. An “acceptor” moiety is likely to accept theelectrons from the “donor” moiety into its LUMO. The donor-acceptornature of TADF molecules results in low-lying excited states withcharge-transfer character that exhibit very low A. Since thermalmolecular motions can randomly vary the optical properties ofdonor-acceptor systems, a rigid three-dimensional arrangement of donorand acceptor moieties can be used to limit the non-radiative decay ofthe charge-transfer state by internal conversion during the lifetime ofthe excitation.

It is beneficial, therefore, to decrease energetic splitting betweensinglet and triplet states (A), and to create a system with increasedreversed intersystem crossing (RISC) capable of exploiting tripletexcitons. Such a system, it is believed, will result in decreasedemission lifetimes. Systems with these features will be capable ofemitting blue light without being subject to the rapid degradationprevalent in blue OLEDs known today.

Compounds of the Disclosure

In some embodiments, the compounds have a structure of Formula (I):

wherein

A is independently selected from

X^(A) is independently selected from O, S, and NR^(A′);

R^(A) is independently selected from hydrogen, deuterium, halogen,cyano, substituted or unsubstituted alkyl, substituted or unsubstitutedalkoxy, substituted or unsubstituted aryl, substituted or unsubstitutedaryloxy, substituted or unsubstituted heteroaryl, substituted orunsubstituted heteroaryloxy, and silyl;

two or more instances of R^(A) taken together can form a ring system;

R^(A′) is independently selected from hydrogen, deuterium, substitutedor unsubstituted alkyl, substituted or unsubstituted aryl, andsubstituted or unsubstituted heteroaryl;

two or more instances of R^(A′) and R^(A) taken together can form a ringsystem;

D is independently selected from

X^(D) is independently selected from a bond, O, S, NR^(D′), C(O),substituted or unsubstituted methylene, substituted or unsubstitutedethylene, substituted or unsubstituted vinylene, substituted orunsubstituted o-arylene, and substituted or unsubstitutedo-heteroarylene; wherein each instance of methylene, ethylene, vinylene,o-arylene or o-heteroarylene can be substituted with one or moresubstituents independently selected from deuterium, substituted orunsubstituted alkyl, substituted or unsubstituted aryl, and substitutedor unsubstituted heteroaryl;

two or more instances of X^(D) taken together can form a ring system;

R^(D) is independently selected from hydrogen, deuterium, substituted orunsubstituted alkyl, substituted or unsubstituted alkoxy, substituted orunsubstituted amino, substituted or unsubstituted aryl, substituted orunsubstituted aryloxy, substituted or unsubstituted heteroaryl,substituted or unsubstituted heteroaryloxy, and silyl;

two or more instances of R^(D) taken together can form a ring system;

R^(D′) is independently selected from hydrogen, deuterium, substitutedor unsubstituted alkyl, substituted or unsubstituted amino, substitutedor unsubstituted aryl, and substituted or unsubstituted heteroaryl;

two or more instances of R^(D′) and R^(D) taken together can form a ringsystem;

L^(A) and L^(D) are independently selected from single bond, substitutedor unsubstituted arylene, and substituted or unsubstituted heteroarylenegroup; wherein each instance of arylene and heteroarylene can besubstituted with one or more substituents independently selected fromdeuterium, substituted or unsubstituted alkyl, substituted orunsubstituted aryl, and substituted or unsubstituted heteroaryl; two ormore of these substituents taken together can form a ring system;

Ar is independently selected from substituted or unsubstituted aryl andsubstituted or unsubstituted heteroaryl group, wherein the substitutedor unsubstituted heteroaryl group does not contain a ring nitrogen atom;each substituent is independently selected from deuterium, substitutedor unsubstituted alkyl, substituted or unsubstituted aryl, andsubstituted or unsubstituted heteroaryl; two or more of thesesubstituents taken together can form a ring system;

k is 1 or 2;

n is 1 to 4;

m is 0 to 3

(k+m+n) is 2 to 6; and

each “*” represents a point of attachment to Formula (I);

provided that if n is greater than or equal to 2, then L^(A) is not asingle bond.

In some embodiments, alkyl is C1-C20-alkyl. In some embodiments, alkylis C1-C12 alkyl. In some embodiments, aryl is C6-C40 aryl. In someembodiments, aryl is C6-C25 aryl. In some embodiments, heteroaryl isC2-C40 heteroaryl. In some embodiments, heteroaryl is C2-C25 heteroaryl.In some embodiments, alkoxy is C1-C20 alkoxy. In some embodiments,alkoxy is C1-C12 alkoxy. In some embodiments, aryloxy is C6-C40 aryloxy.In some embodiments, aryloxy is C6-C25 aryloxy. In some embodiments,heteroaryloxy is C3-C40 heteroaryloxy. In some embodiments,heteroaryloxy is C3-C25 heteroaryloxy.

In some embodiments, wherein D is

In some embodiments, D is

In some embodiments, D is

In some embodiments, D is

In some embodiments, D is

In some embodiments, D is selected from

In some embodiments, X^(D) is O. In some embodiments, X^(D) is S. Insome embodiments, X^(D) is NR^(D′). In some embodiments, X^(D) is C(O).In some embodiments, X° is substituted or unsubstituted methylene. Insome embodiments, X^(D) is substituted or unsubstituted ethylene. Insome embodiments, X^(D) is substituted or unsubstituted vinylene. Insome embodiments, X^(D) is substituted or unsubstituted o-arylene. Insome embodiments, X^(D) is and substituted or unsubstitutedo-heteroarylene. In some embodiments, methylene, ethylene, vinylene,o-arylene and o-heteroarylene can be substituted with deuterium,substituted or unsubstituted alkyl, substituted or unsubstituted aryl,and substituted or unsubstituted heteroaryl. In some embodiments, two ormore instances of X^(D) taken together can form a ring system.

In some embodiments, R^(D) is hydrogen. In some embodiments, R^(D) isdeuterium. In some embodiments, R^(D) is substituted or unsubstitutedalkyl. In some embodiments, R^(D) is substituted or unsubstitutedalkoxy. In some embodiments, R^(D) is substituted or unsubstitutedamino. In some embodiments, R^(D) is substituted or unsubstituted aryl.In some embodiments, R^(D) is substituted or unsubstituted aryloxy. Insome embodiments, R^(D) is substituted or unsubstituted heteroaryl. Insome embodiments, R^(D) is substituted or unsubstituted heteroaryloxy.In some embodiments, R^(D) is silyl. In some embodiments, two or moreinstances of R^(D) taken together can form a ring system.

In some embodiments, R^(D′) is hydrogen. In some embodiments, R^(D′) isdeuterium. In some embodiments, R^(D′) is substituted or unsubstitutedalkyl. In some embodiments, R^(D′) is substituted or unsubstitutedamino. In some embodiments, R^(D′) is substituted or unsubstituted aryl.In some embodiments, R^(D′) is substituted or unsubstituted heteroaryl.In some embodiments, two or more instances of R^(D′) and R^(D) takentogether can form a ring system.

In some embodiments, L^(D) is a single bond. In some embodiments, L^(D)is substituted or unsubstituted arylene. In some embodiments, L^(D) issubstituted or unsubstituted heteroarylene.

In some embodiments, when L^(D) is substituted each substituent isindependently selected from deuterium, substituted or unsubstitutedalkyl, substituted or unsubstituted aryl, and substituted orunsubstituted heteroaryl; two or more of these substituents takentogether can form a ring system.

In some embodiments, Ar is substituted or unsubstituted aryl. In someembodiments, Ar is substituted or unsubstituted heteroaryl. In someembodiments, the substituted or unsubstituted heteroaryl group does notcontain any nitrogen atoms; each substituent is independently selectedfrom deuterium, substituted or unsubstituted alkyl, substituted orunsubstituted aryl, and substituted or unsubstituted heteroaryl; two ormore of these substituents taken together can form a ring system.

In some embodiments, two instances of A have an ortho relationship. Insome embodiments, two instances of A have a meta relationship. In someembodiments, two instances of A have a para relationship.

In some embodiments, n is 1. In some embodiments, n is 2. In someembodiments, n is 3. In some embodiments, n is 4.

In some embodiments, m is 0. In some embodiments, m is 1. In someembodiments, m is 2. In some embodiments, m is 3.

In some embodiments, k is 1. In some embodiments, k is 2.

In some embodiments, (k+m+n) is 3. In some embodiments, (k+m+n) is 4. Insome embodiments, (k+m+n) is 5. In some embodiments, (k+m+n) is 6.

The compound of claim 1, wherein the compound of Formula (I) isrepresented by Formula (Ia):

The compound of claim 1, wherein the compound is

In some embodiments, the compound of Formula (I) is represented byFormula (Ib)

In some embodiments, the compound is

In some embodiments, the compound is

In some embodiments, the compounds have a structure of Formula (II):

wherein

A is independently selected from

R₁, R₂, R₃, and R₄ are independently selected from D, H, and Ph;

D is independently selected from

at least one instance of D is present;

0 to 3 instances of H are present;

0 to 3 instances of Ph are present; and

if R₃ is D, then at least one of R₁, R₂, R₄ is not H; and

if R₂ is D and R₄ is D, then at least one of R₁ or R₃ is not H.

In some embodiments, A is selected from A1, A2, and A3. In someembodiments, A is selected from A4 and A5. In some embodiments, A is A1.In some embodiments, A is A2. In some embodiments, A is A3. In someembodiments, A is A4. In some embodiments, A is A5.

In some embodiments, D is selected from D1, D2, and D3. In someembodiments, D is selected from D4, D5 and D6. In some embodiments, D isselected from D7, D8, and D9. In some embodiments, D is selected fromD10, D11, D12, and D13. In some embodiments, D is D1. In someembodiments, D is D2. In some embodiments, D is D3. In some embodiments,D is D4. In some embodiments, D is D5. In some embodiments, D is D6. Insome embodiments, D is D7. In some embodiments, D is D8. In someembodiments, D is D9. In some embodiments, D is D10. In someembodiments, D is D11. In some embodiments, D is D12. In someembodiments, D is D13.

In some embodiments, R₁ is D. In some embodiments. In some embodiments,R₁ is H. In some embodiments, R₁ is Ph.

In some embodiments, R₂ is D. In some embodiments. In some embodiments,R₂ is H. In some embodiments, R₂ is Ph.

In some embodiments, R₃ is D. In some embodiments. In some embodiments,R₃ is H. In some embodiments, R₃ is Ph.

In some embodiments, R₄ is D. In some embodiments. In some embodiments,R₄ is H. In some embodiments, R₄ is Ph.

In some embodiments, two instances of D, one H, and one Ph are present.In some embodiments, two instances of H, and one Ph are present. In someembodiments one D, one H, and two instances of Ph are present. In someembodiments, three instances of D, and one H are present. In someembodiments, three instances of D, and one Ph are present.

In some embodiments, R₁ and R₂ are D. In some embodiments, R₁ and R₃ areD. In some embodiments, R₁ and R₄ are D. In some embodiments, R₂ and R₃are D. In some embodiments, R₂ and R₄ are D. In some embodiments, R₃ andR₄ are D. In some embodiments, R₁, R₂, and R₃ are D. In someembodiments, R₁ and R₃ are D. In some embodiments, R₁ and R₄ are D. Insome embodiments, R₂ and R₃ are D. In some embodiments, R₃ and R₄ are D.

In some embodiments, the compound of claim 1, selected from

-   9-(2-(3,6-dimethyl-9H-carbazol-9-yl)-3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-2-(2,6-diphenylpyridin-4-yl)-6-phenyl-9H-carbazole-   9-(2-(3,6-dimethyl-9H-carbazol-9-yl)-3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-6-phenyl-2-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(2-(3,6-dimethyl-9H-carbazol-9-yl)-4,6-bis(2,6-diphenylpyrimidin-4-yl)phenyl)-2-(2,6-diphenylpyridin-4-yl)-6-phenyl-9H-carbazole-   9-(2-(3,6-dimethyl-9H-carbazol-9-yl)-4,6-bis(2,6-diphenylpyrimidin-4-yl)phenyl)-2,7-bis(6-phenylpyridin-2-yl)-9H-carbazole-   9-(2-(3,6-dimethyl-9H-carbazol-9-yl)-4,6-bis(4,6-diphenylpyrimidin-2-yl)phenyl)-6-phenyl-2-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(2-(9H-carbazol-9-yl)-3,5-bis(2,6-diphenylpyrimidin-4-yl)phenyl)-3-methyl-9H-carbazole-   9-(2-(9H-carbazol-9-yl)-3,5-bis(2,6-diphenylpyrimidin-4-yl)phenyl)-3,6-diphenyl-9H-carbazole-   9-(2-(9H-carbazol-9-yl)-3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-2-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(2-(9H-carbazol-9-yl)-3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-3-phenyl-6-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(2-(9H-carbazol-9-yl)-3,5-bis(4,6-diphenylpyrimidin-2-yl)phenyl)-3,6-dimethyl-9H-carbazole-   9-(2-(9H-carbazol-9-yl)-3,5-bis(4,6-diphenylpyrimidin-2-yl)phenyl)-3,6-diphenyl-9H-carbazole-   9-(2,4-bis(2,6-diphenylpyrimidin-4-yl)-3-(3-phenyl-6-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-3,6-dimethyl-9H-carbazole-   9-(2,4-bis(2,6-diphenylpyrimidin-4-yl)-5-(3-phenyl-9H-carbazol-9-yl)phenyl)-3,6-dimethyl-9H-carbazole-   9-(2,4-bis(2,6-diphenylpyrimidin-4-yl)-6-(2-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-6-phenyl-2-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(2,4-bis(2,6-diphenylpyrimidin-4-yl)-6-(3-methyl-9H-carbazol-9-yl)phenyl)-3-phenyl-6-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(2,4-bis(2,6-diphenylpyrimidin-4-yl)-6-(3-methyl-9H-carbazol-9-yl)phenyl)-3,6-dimethyl-9H-carbazole-   9-(2,4-bis(2,6-diphenylpyrimidin-4-yl)-6-(3-phenyl-9H-carbazol-9-yl)phenyl)-3-phenyl-6-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(2,4-bis(2,6-diphenylpyrimidin-4-yl)-6-(3-phenyl-9H-carbazol-9-yl)phenyl)-6-phenyl-2-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(2,4-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-3-(3-methyl-9H-carbazol-9-yl)phenyl)-3-phenyl-9H-carbazole-   9-(2,4-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-3-(3-phenyl-6-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-3,6-dimethyl-9H-carbazole-   9-(2,4-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-5-(3-methyl-9H-carbazol-9-yl)phenyl)-2-(2,6-diphenylpyridin-4-yl)-6-phenyl-9H-carbazole-   9-(2,4-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-5-(3-phenyl-9H-carbazol-9-yl)phenyl)-3,6-bis(6-phenylpyridin-2-yl)-9H-carbazole-   9-(2,4-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-6-(3-phenyl-9H-carbazol-9-yl)phenyl)-3,6-dimethyl-9H-carbazole-   9-(2,4-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-6-(3-phenyl-9H-carbazol-9-yl)phenyl)-3,6-diphenyl-9H-carbazole-   9-(2,4-bis(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-2-(2,6-diphenylpyridin-4-yl)-6-phenyl-9H-carbazole-   9-(2,4-bis(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-6-phenyl-2-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(2,4-bis(4,6-diphenylpyrimidin-2-yl)-3-(3-methyl-9H-carbazol-9-yl)phenyl)-2-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(2,4-bis(4,6-diphenylpyrimidin-2-yl)-6-(3-methyl-9H-carbazol-9-yl)phenyl)-3-phenyl-6-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(2,6-bis(2,6-diphenylpyrimidin-4-yl)-3-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-3,6-diphenyl-9H-carbazole-   9-(2,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-3-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-3-methyl-9H-carbazole-   9-(2,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-3-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-3,6-diphenyl-9H-carbazole-   9-(2,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-3-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-6-phenyl-2-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(2,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-3-(3-methyl-9H-carbazol-9-yl)phenyl)-2-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(2,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-3-(3-methyl-9H-carbazol-9-yl)phenyl)-6-phenyl-2-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(2,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-3-(3-phenyl-9H-carbazol-9-yl)phenyl)-3-(2,6-diphenylpyridin-4-yl)-6-phenyl-9H-carbazole-   9-(2,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-3-(3,6-diphenyl-9H-carbazol-9-yl)phenyl)-3-phenyl-6-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(2,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-3-(3,6-diphenyl-9H-carbazol-9-yl)phenyl)-3,6-dimethyl-9H-carbazole-   9-(2,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-4-(2-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-6-phenyl-2-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(2,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-4-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-2-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(2,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-4-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-3,6-diphenyl-9H-carbazole-   9-(2,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-4-(3-methyl-9H-carbazol-9-yl)phenyl)-3-(2,6-diphenylpyridin-4-yl)-6-phenyl-9H-carbazole-   9-(2,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-4-(3-methyl-9H-carbazol-9-yl)phenyl)-3-phenyl-9H-carbazole-   9-(2,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-4-(3-phenyl-9H-carbazol-9-yl)phenyl)-3,6-diphenyl-9H-carbazole-   9-(2,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-3,6-diphenyl-9H-carbazole-   9-(2,6-bis(4,6-diphenylpyrimidin-2-yl)-3-(2-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-3,6-dimethyl-9H-carbazole-   9-(2,6-bis(4,6-diphenylpyrimidin-2-yl)-3-(2-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-3,6-diphenyl-9H-carbazole-   9-(2,6-bis(4,6-diphenylpyrimidin-2-yl)-3-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-3,6-dimethyl-9H-carbazole-   9-(2,6-bis(4,6-diphenylpyrimidin-2-yl)-4-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-3-phenyl-9H-carbazole-   9-(2,6-bis(4,6-diphenylpyrimidin-2-yl)-4-(3-methyl-9H-carbazol-9-yl)phenyl)-6-phenyl-2-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(2,6-bis(4,6-diphenylpyrimidin-2-yl)-4-(3-phenyl-9H-carbazol-9-yl)phenyl)-3-phenyl-6-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(2,6-bis(4,6-diphenylpyrimidin-2-yl)phenyl)-3-methyl-9H-carbazole-   9-(2,6-bis(4,6-diphenylpyrimidin-2-yl)phenyl)-3,6-diphenyl-9H-carbazole-   9-(3-(3,6-dimethyl-9H-carbazol-9-yl)-2,4-bis(2,6-diphenylpyrimidin-4-yl)phenyl)-3,6-diphenyl-9H-carbazole-   9-(3-(3,6-dimethyl-9H-carbazol-9-yl)-2,4-bis(4,6-diphenylpyrimidin-2-yl)phenyl)-3,6-diphenyl-9H-carbazole-   9-(3-(9H-carbazol-9-yl)-2,4-bis(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-2-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(3-(9H-carbazol-9-yl)-2,4-bis(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-3,6-dimethyl-9H-carbazole-   9-(3-(9H-carbazol-9-yl)-2,4-bis(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-6-phenyl-2-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(3-(9H-carbazol-9-yl)-2,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-2-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(3-(9H-carbazol-9-yl)-2,6-bis(4,6-diphenylpyrimidin-2-yl)phenyl)-3,6-dimethyl-9H-carbazole-   9-(3,5-bis(2,6-diphenylpyrimidin-4-yl)-2-(2-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-3,6-dimethyl-9H-carbazole-   9-(3,5-bis(2,6-diphenylpyrimidin-4-yl)-2-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-3-phenyl-9H-carbazole-   9-(3,5-bis(2,6-diphenylpyrimidin-4-yl)-2-(3-methyl-9H-carbazol-9-yl)phenyl)-3,6-diphenyl-9H-carbazole-   9-(3,5-bis(2,6-diphenylpyrimidin-4-yl)-2-(3-phenyl-9H-carbazol-9-yl)phenyl)-3-(2,6-diphenylpyridin-4-yl)-6-phenyl-9H-carbazole-   9-(3,5-bis(2,6-diphenylpyrimidin-4-yl)-2-(3-phenyl-9H-carbazol-9-yl)phenyl)-3-methyl-9H-carbazole-   9-(3,5-bis(2,6-diphenylpyrimidin-4-yl)-2-(3-phenyl-9H-carbazol-9-yl)phenyl)-3,6-diphenyl-9H-carbazole-   9-(3,5-bis(2,6-diphenylpyrimidin-4-yl)-4-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-3,6-diphenyl-9H-carbazole-   9-(3,5-bis(2,6-diphenylpyrimidin-4-yl)phenyl)-3-(2,6-diphenylpyridin-4-yl)-6-phenyl-9H-carbazole-   9-(3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-2-(2-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-3,6-dimethyl-9H-carbazole-   9-(3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-2-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-3-phenyl-9H-carbazole-   9-(3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-2-(3-methyl-9H-carbazol-9-yl)phenyl)-2,7-bis(6-phenylpyridin-2-yl)-9H-carbazole-   9-(3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-2-(3-phenyl-6-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-3,6-dimethyl-9H-carbazole-   9-(3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-2-(3,6-diphenyl-9H-carbazol-9-yl)phenyl)-3,6-dimethyl-9H-carbazole-   9-(3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-4-(2-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-3-phenyl-6-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-4-(2-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-3,6-dimethyl-9H-carbazole-   9-(3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-4-(2-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-3,6-diphenyl-9H-carbazole-   9-(3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-4-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-2-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-4-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-3-phenyl-6-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-4-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-3,6-diphenyl-9H-carbazole-   9-(3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-4-(3-phenyl-6-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-3,6-dimethyl-9H-carbazole-   9-(3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-4-(3-phenyl-9H-carbazol-9-yl)phenyl)-2,7-bis(6-phenylpyridin-2-yl)-9H-carbazole-   9-(3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-4-(3-phenyl-9H-carbazol-9-yl)phenyl)-3-(2,6-diphenylpyridin-4-yl)-6-phenyl-9H-carbazole-   9-(3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-4-(3-phenyl-9H-carbazol-9-yl)phenyl)-3-phenyl-6-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-3-phenyl-6-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(3,5-bis(4,6-diphenylpyrimidin-2-yl)-2-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-3,6-dimethyl-9H-carbazole-   9-(3,5-bis(4,6-diphenylpyrimidin-2-yl)-4-(3-methyl-9H-carbazol-9-yl)phenyl)-2-(2,6-diphenylpyridin-4-yl)-6-phenyl-9H-carbazole-   9-(3,5-bis(4,6-diphenylpyrimidin-2-yl)-4-(3-methyl-9H-carbazol-9-yl)phenyl)-2-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(3,5-bis(4,6-diphenylpyrimidin-2-yl)-4-(3-methyl-9H-carbazol-9-yl)phenyl)-3,6-bis(6-phenylpyridin-2-yl)-9H-carbazole-   9-(3,5-bis(4,6-diphenylpyrimidin-2-yl)-4-(3-methyl-9H-carbazol-9-yl)phenyl)-3,6-diphenyl-9H-carbazole-   9-(3,5-bis(4,6-diphenylpyrimidin-2-yl)-4-(3-phenyl-6-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-3,6-dimethyl-9H-carbazole-   9-(3,5-bis(4,6-diphenylpyrimidin-2-yl)-4-(3-phenyl-9H-carbazol-9-yl)phenyl)-3,6-diphenyl-9H-carbazole-   9-(4-(3,6-dimethyl-9H-carbazol-9-yl)-3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-2,7-bis(6-phenylpyridin-2-yl)-9H-carbazole-   9-(4-(9H-carbazol-9-yl)-2,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-3-methyl-9H-carbazole-   9-(4-(9H-carbazol-9-yl)-2,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-3-phenyl-6-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(4-(9H-carbazol-9-yl)-2,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-3,6-bis(6-phenylpyridin-2-yl)-9H-carbazole-   9-(4-(9H-carbazol-9-yl)-2,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-3,6-dimethyl-9H-carbazole-   9-(4-(9H-carbazol-9-yl)-2,6-bis(4,6-diphenylpyrimidin-2-yl)phenyl)-3,6-diphenyl-9H-carbazole-   9-(4-(9H-carbazol-9-yl)-3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-3-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(4-(9H-carbazol-9-yl)-3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-3-phenyl-9H-carbazole-   9-(5-(9H-carbazol-9-yl)-2,4-bis(2,6-diphenylpyrimidin-4-yl)phenyl)-3-phenyl-9H-carbazole-   9-(5-(9H-carbazol-9-yl)-2,4-bis(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-3-methyl-9H-carbazole-   9-(5-(9H-carbazol-9-yl)-2,4-bis(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-3,6-dimethyl-9H-carbazole    9,9′-(2-(3-phenyl-6-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-4,6-bis(6-phenylpyridin-2-yl)-1,3-phenylene)bis(3-methyl-9H-carbazole)    9,9′-(2-(3,6-dimethyl-9H-carbazol-9-yl)-3,5-bis(2,6-diphenylpyridin-4-yl)-1,4-phenylene)bis(3-phenyl-9H-carbazole)    9,9′-(2-(3,6-dimethyl-9H-carbazol-9-yl)-3,5-bis(2,6-diphenylpyrimidin-4-yl)-1,4-phenylene)bis(9H-carbazole)    9,9′-(2-(3,6-diphenyl-9H-carbazol-9-yl)-4,6-bis(2,6-diphenylpyridin-4-yl)-1,3-phenylene)bis(3-methyl-9H-carbazole)    9,9′-(2-(3,6-diphenyl-9H-carbazol-9-yl)-4,6-bis(2,6-diphenylpyrimidin-4-yl)-1,3-phenylene)bis(3-methyl-9H-carbazole)    9,9′-(2-(9H-carbazol-9-yl)-3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,4-phenylene)bis(3-methyl-9H-carbazole)    9,9′-(2,4-bis(2,6-diphenylpyrimidin-4-yl)-1,3-phenylene)bis(3,6-diphenyl-9H-carbazole)    9,9′-(2,4-bis(2,6-diphenylpyrimidin-4-yl)-6-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-1,3-phenylene)bis(3-methyl-9H-carbazole)    9,9′-(2,4-bis(2,6-diphenylpyrimidin-4-yl)-6-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-1,3-phenylene)bis(9H-carbazole)    9,9′-(2,4-bis(2,6-diphenylpyrimidin-4-yl)-6-(3-phenyl-9H-carbazol-9-yl)-1,3-phenylene)bis(3,6-dimethyl-9H-carbazole)    9,9′-(2,4-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,3-phenylene)bis(2-(6-phenylpyridin-2-yl)-9H-carbazole)    9,9′-(2,4-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,3-phenylene)bis(9H-carbazole)    9,9′-(2,4-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-6-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-1,3-phenylene)bis(3-methyl-9H-carbazole)    9,9′-(2,4-bis(4,6-diphenylpyrimidin-2-yl)-1,3-phenylene)bis(9H-carbazole)    9,9′-(2,4-bis(4,6-diphenylpyrimidin-2-yl)-6-(2-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-1,3-phenylene)bis(3,6-dimethyl-9H-carbazole)    9,9′-(2,6-bis(2,6-diphenylpyrimidin-4-yl)-1,4-phenylene)bis(3-(6-phenylpyridin-2-yl)-9H-carbazole)    9,9′-(2,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,4-phenylene)bis(3,6-dimethyl-9H-carbazole)    9,9′-(2,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,4-phenylene)bis(3,6-diphenyl-9H-carbazole)    9,9′-(2,6-bis(4,6-diphenylpyrimidin-2-yl)-1,4-phenylene)bis(3-phenyl-9H-carbazole)    9,9′-(3,5-bis(2,6-diphenylpyrimidin-4-yl)-1,2-phenylene)bis(3,6-dimethyl-9H-carbazole)    9,9′-(3,5-bis(2,6-diphenylpyrimidin-4-yl)-2-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-1,4-phenylene)bis(3-methyl-9H-carbazole)    9,9′-(3,5-bis(2,6-diphenylpyrimidin-4-yl)-2-(3-methyl-9H-carbazol-9-yl)-1,4-phenylene)bis(9H-carbazole)    9,9′-(3,5-bis(2,6-diphenylpyrimidin-4-yl)-2-(3-phenyl-6-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-1,4-phenylene)bis(3-methyl-9H-carbazole)    9,9′-(3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,2-phenylene)bis(3,6-dimethyl-9H-carbazole)    9,9′-(3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-2-(3-methyl-9H-carbazol-9-yl)-1,4-phenylene)bis(3,6-dimethyl-9H-carbazole)    9,9′-(3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-2-(3-methyl-9H-carbazol-9-yl)-1,4-phenylene)bis(9H-carbazole)    9,9′-(3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-2-(3-phenyl-9H-carbazol-9-yl)-1,4-phenylene)bis(3-methyl-9H-carbazole)    9,9′-(3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-4-(3-methyl-9H-carbazol-9-yl)-1,2-phenylene)bis(3,6-dimethyl-9H-carbazole)    9,9′-(3,5-bis(4,6-diphenylpyrimidin-2-yl)-1,2-phenylene)bis(3,6-diphenyl-9H-carbazole)    9,9′-(3,5-bis(4,6-diphenylpyrimidin-2-yl)-2-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-1,4-phenylene)bis(9H-carbazole)    9,9′-(3,5-bis(4,6-diphenylpyrimidin-2-yl)-2-(6-phenyl-2-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-1,4-phenylene)bis(9H-carbazole)    9,9′-(4-(3-phenyl-9H-carbazol-9-yl)-3,5-bis(6-phenylpyridin-2-yl)-1,2-phenylene)bis(9H-carbazole)    9,9′-(4-(3,6-dimethyl-9H-carbazol-9-yl)-2,6-bis(2,6-diphenylpyrimidin-4-yl)-1,3-phenylene)bis(3-methyl-9H-carbazole)    9,9′-(4-(3,6-dimethyl-9H-carbazol-9-yl)-2,6-bis(2,6-diphenylpyrimidin-4-yl)-1,3-phenylene)bis(9H-carbazole)    9,9′-(4-(3,6-dimethyl-9H-carbazol-9-yl)-2,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,3-phenylene)bis(3-phenyl-9H-carbazole)    9,9′-(4-(3,6-dimethyl-9H-carbazol-9-yl)-3,5-bis(2,6-diphenylpyrimidin-4-yl)-1,2-phenylene)bis(3-methyl-9H-carbazole)    9,9′-(4-(3,6-dimethyl-9H-carbazol-9-yl)-3,5-bis(2,6-diphenylpyrimidin-4-yl)-1,2-phenylene)bis(9H-carbazole)    9,9′-(4-(3,6-dimethyl-9H-carbazol-9-yl)-3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,2-phenylene)bis(9H-carbazole)    9,9′-(4-(3,6-dimethyl-9H-carbazol-9-yl)-3,5-bis(4,6-diphenylpyrimidin-2-yl)-1,2-phenylene)bis(9H-carbazole)    9,9′-(4-(3,6-dimethyl-9H-carbazol-9-yl)-3,5-bis(6-phenylpyridin-2-yl)-1,2-phenylene)bis(3-(6-phenylpyridin-2-yl)-9H-carbazole)    9,9′-(4-(9H-carbazol-9-yl)-2,6-bis(2,6-diphenylpyridin-4-yl)-1,3-phenylene)bis(3,6-dimethyl-9H-carbazole)    9,9′-(4-(9H-carbazol-9-yl)-2,6-bis(2,6-diphenylpyrimidin-4-yl)-1,3-phenylene)bis(3-methyl-9H-carbazole)    9,9′-(4-(9H-carbazol-9-yl)-2,6-bis(2,6-diphenylpyrimidin-4-yl)-1,3-phenylene)bis(3-phenyl-9H-carbazole)    9,9′-(4,6-bis(2,6-diphenylpyridin-4-yl)-2-(2-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-1,3-phenylene)bis(3,6-dimethyl-9H-carbazole)    9,9′-(4,6-bis(2,6-diphenylpyridin-4-yl)-2-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-1,3-phenylene)bis(9H-carbazole)    9,9′-(4,6-bis(2,6-diphenylpyridin-4-yl)-2-(3-phenyl-9H-carbazol-9-yl)-1,3-phenylene)bis(3,6-dimethyl-9H-carbazole)    9,9′-(4,6-bis(2,6-diphenylpyrimidin-4-yl)-2-(2-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-1,3-phenylene)bis(3-methyl-9H-carbazole)    9,9′-(4,6-bis(2,6-diphenylpyrimidin-4-yl)-5-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-1,3-phenylene)bis(3-methyl-9H-carbazole)    9,9′-(4,6-bis(2,6-diphenylpyrimidin-4-yl)-5-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-1,3-phenylene)bis(3,6-dimethyl-9H-carbazole)    9,9′-(4,6-bis(2,6-diphenylpyrimidin-4-yl)-5-(3-phenyl-9H-carbazol-9-yl)-1,3-phenylene)bis(3-methyl-9H-carbazole)    9,9′-(4,6-bis(2,6-diphenylpyrimidin-4-yl)-5-(3-phenyl-9H-carbazol-9-yl)-1,3-phenylene)bis(9H-carbazole)    9,9′-(4,6-bis(2,6-diphenylpyrimidin-4-yl)-5-(6-phenyl-2-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-1,3-phenylene)bis(9H-carbazole)    9,9′-(4,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,3-phenylene)bis(2-(6-phenylpyridin-2-yl)-9H-carbazole)    9,9′-(4,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,3-phenylene)bis(3-(6-phenylpyridin-2-yl)-9H-carbazole)    9,9′-(4,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-2-(2-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-1,3-phenylene)bis(3-methyl-9H-carbazole)    9,9′-(4,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-2-(3-phenyl-9H-carbazol-9-yl)-1,3-phenylene)bis(3,6-dimethyl-9H-carbazole)    9,9′-(4,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-2-(3-phenyl-9H-carbazol-9-yl)-1,3-phenylene)bis(9H-carbazole)    9,9′-(4,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-2-(3,6-diphenyl-9H-carbazol-9-yl)-1,3-phenylene)bis(9H-carbazole)    9,9′-(4,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-5-(2-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-1,3-phenylene)bis(3-methyl-9H-carbazole)    9,9′-(4,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-5-(3-phenyl-9H-carbazol-9-yl)-1,3-phenylene)bis(3-methyl-9H-carbazole)    9,9′-(4,6-bis(4,6-diphenylpyrimidin-2-yl)-5-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-1,3-phenylene)bis(3-methyl-9H-carbazole)    9,9′-(4,6-bis(4,6-diphenylpyrimidin-2-yl)-5-(3-methyl-9H-carbazol-9-yl)-1,3-phenylene)bis(3-phenyl-9H-carbazole)    9,9′-(4,6-bis(4,6-diphenylpyrimidin-2-yl)-5-(3-phenyl-9H-carbazol-9-yl)-1,3-phenylene)bis(9H-carbazole)    9,9′,9″-(2,4-bis(4,6-diphenylpyrimidin-2-yl)benzene-1,3,5-triyl)tris(3-methyl-9H-carbazole)    9,9′,9″-(3,5-bis(2,6-diphenylpyrimidin-4-yl)benzene-1,2,4-triyl)tris(3,6-dimethyl-9H-carbazole)    9,9′,9″-(4,6-bis(2,6-diphenylpyridin-4-yl)benzene-1,2,3-triyl)tris(3-methyl-9H-carbazole)    9,9′,9″-(4,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)benzene-1,2,3-triyl)tris(3,6-dimethyl-9H-carbazole)    9,9′,9″-(3,5-bis(2,6-diphenylpyrimidin-4-yl)benzene-1,2,4-triyl)tris(9H-carbazole)    9,9′-(3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-4-(3-methyl-9H-carbazol-9-yl)-1,2-phenylene)bis(9H-carbazole)    9,9′-(4,6-bis(2,6-diphenylpyrimidin-4-yl)-5-(3-methyl-9H-carbazol-9-yl)-1,3-phenylene)bis(3,6-dimethyl-9H-carbazole)-   9-(3-(3,6-bis(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-2,6-bis(4,6-diphenylpyrimidin-2-yl)phenyl)-3,6-dimethyl-9H-carbazole    9,9′-(5-(9H-carbazol-9-yl)-4,6-bis(2,6-diphenylpyrimidin-4-yl)-1,3-phenylene)bis(3-phenyl-9H-carbazole)    9,9′-(4,6-bis(2,6-diphenylpyrimidin-4-yl)-5-(3-phenyl-6-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-1,3-phenylene)bis(9H-carbazole)    9,9′-(4,6-bis(2,6-diphenylpyridin-4-yl)-2-(6-phenyl-2-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-1,3-phenylene)bis(9H-carbazole)    9,9′-(4-(9H-carbazol-9-yl)-3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,2-phenylene)bis(3-phenyl-9H-carbazole)-   9-(2,6-bis(2,6-diphenylpyrimidin-4-yl)-4-(3-phenyl-6-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-3,6-diphenyl-9H-carbazole-   9-(3-(3,6-bis(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-2,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-3,6-dimethyl-9H-carbazole    9,9′-(4,6-bis(4,6-diphenylpyrimidin-2-yl)-2-(3-phenyl-6-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-1,3-phenylene)bis(9H-carbazole)    9,9′-(4,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-2-(3,6-diphenyl-9H-carbazol-9-yl)-1,3-phenylene)bis(3,6-dimethyl-9H-carbazole)    9,9′-(4-(3,6-diphenyl-9H-carbazol-9-yl)-2,6-bis(2,6-diphenylpyrimidin-4-yl)-1,3-phenylene)bis(3,6-dimethyl-9H-carbazole)-   9-(2-(3,6-dimethyl-9H-carbazol-9-yl)-3,5-bis(2,6-diphenylpyrimidin-4-yl)phenyl)-3,6-diphenyl-9H-carbazole-   9-(4-(3,6-bis(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-2,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-3,6-dimethyl-9H-carbazole    9,9′-(3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,2-phenylene)bis(3-(6-phenylpyridin-2-yl)-9H-carbazole)    9,9′-(4,6-bis(2,6-diphenylpyridin-4-yl)-2-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-1,3-phenylene)bis(3,6-dimethyl-9H-carbazole)    9,9′-(3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-4-(6-phenyl-2-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-1,2-phenylene)bis(9H-carbazole)-   9-(2,6-bis(2,6-diphenylpyrimidin-4-yl)-3-(3-phenyl-9H-carbazol-9-yl)phenyl)-3-(2,6-diphenylpyridin-4-yl)-6-phenyl-9H-carbazole-   9-(2,6-bis(2,6-diphenylpyrimidin-4-yl)-4-(3-methyl-9H-carbazol-9-yl)phenyl)-3,6-bis(6-phenylpyridin-2-yl)-9H-carbazole    9,9′-(4,6-bis(4,6-diphenylpyrimidin-2-yl)-1,3-phenylene)bis(3,6-diphenyl-9H-carbazole)    9,9′-(2,4-bis(2,6-diphenylpyrimidin-4-yl)-6-(3-phenyl-6-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-1,3-phenylene)bis(3-methyl-9H-carbazole)    9,9′-(5-(3,6-diphenyl-9H-carbazol-9-yl)-4,6-bis(2,6-diphenylpyrimidin-4-yl)-1,3-phenylene)bis(3,6-dimethyl-9H-carbazole)-   9-(4-(3,6-dimethyl-9H-carbazol-9-yl)-3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-2-(2,6-diphenylpyridin-4-yl)-6-phenyl-9H-carbazole-   9-(2-(3,6-bis(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-4,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-3,6-dimethyl-9H-carbazole    9,9′-(3,5-bis(4,6-diphenylpyrimidin-2-yl)-4-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-1,2-phenylene)bis(3-methyl-9H-carbazole)    9,9′-(3,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-2-(3-methyl-9H-carbazol-9-yl)-1,4-phenylene)bis(3-phenyl-9H-carbazole)    9,9′-(2,4-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-6-(3,6-diphenyl-9H-carbazol-9-yl)-1,3-phenylene)bis(9H-carbazole)-   9-(3,5-bis(2,6-diphenylpyrimidin-4-yl)-2-(3-phenyl-9H-carbazol-9-yl)phenyl)-3,6-bis(6-phenylpyridin-2-yl)-9H-carbazole-   9-(3,5-bis(4,6-diphenylpyrimidin-2-yl)-4-(3-phenyl-6-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)phenyl)-3,6-diphenyl-9H-carbazole    9,9′-(2,4-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-6-(3,6-diphenyl-9H-carbazol-9-yl)-1,3-phenylene)bis(3-methyl-9H-carbazole)    9,9′-(4,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-5-(3-phenyl-6-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-1,3-phenylene)bis(3-methyl-9H-carbazole)-   9-(2,4-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-5-(3-methyl-9H-carbazol-9-yl)phenyl)-6-phenyl-2-(6-phenylpyridin-2-yl)-9H-carbazole-   9-(2,4-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-5-(3-methyl-9H-carbazol-9-yl)phenyl)-3,6-bis(6-phenylpyridin-2-yl)-9H-carbazole    9,9′-(4,6-bis(4,6-diphenylpyrimidin-2-yl)-2-(3-phenyl-9H-carbazol-9-yl)-1,3-phenylene)bis(3-methyl-9H-carbazole)    9,9′-(2-(9H-carbazol-9-yl)-4,6-bis(4,6-diphenylpyrimidin-2-yl)-1,3-phenylene)bis(3-methyl-9H-carbazole)    9,9′-(5-(9H-carbazol-9-yl)-4,6-bis(2,6-diphenylpyrimidin-4-yl)-1,3-phenylene)bis(3,6-dimethyl-9H-carbazole)    9,9′,9″-(4,6-bis(4,6-diphenylpyrimidin-2-yl)benzene-1,2,3-triyl)tris(3,6-dimethyl-9H-carbazole)    9,9′-(2-(3,6-diphenyl-9H-carbazol-9-yl)-4,6-bis(4,6-diphenylpyrimidin-2-yl)-1,3-phenylene)bis(3,6-dimethyl-9H-carbazole)    9,9′-(4,6-bis(4,6-diphenylpyrimidin-2-yl)-2-(3-(6-phenylpyridin-2-yl)-9H-carbazol-9-yl)-1,3-phenylene)bis(3,6-dimethyl-9H-carbazole)    9,9′-(2-(3,6-dimethyl-9H-carbazol-9-yl)-4,6-bis(4,6-diphenylpyrimidin-2-yl)-1,3-phenylene)bis(3-phenyl-9H-carbazole)    9,9′-(4,6-bis(4,6-diphenylpyrimidin-2-yl)-2-(3-methyl-9H-carbazol-9-yl)-1,3-phenylene)bis(3-phenyl-9H-carbazole)    9,9′-(4,6-bis(2,6-diphenylpyridin-4-yl)-2-(3-methyl-9H-carbazol-9-yl)-1,3-phenylene)bis(3,6-dimethyl-9H-carbazole)-   9-(2,4-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-5-(3-phenyl-9H-carbazol-9-yl)phenyl)-2,7-bis(6-phenylpyridin-2-yl)-9H-carbazole-   9-(2,4-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-5-(3-phenyl-9H-carbazol-9-yl)phenyl)-3-(2,6-diphenylpyridin-4-yl)-6-phenyl-9H-carbazole    9,9′,9″-(4,6-bis(4,6-diphenylpyrimidin-2-yl)benzene-1,2,3-triyl)tris(9H-carbazole)-   9-(2-(9H-carbazol-9-yl)-4,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl)-3-(2,6-diphenylpyridin-4-yl)-6-phenyl-9H-carbazole,    and-   9,9′-(4,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,3-phenylene)bis(9H-carbazole).

In some embodiments the compound of Formula (II) is selected from

In some embodiments, the compounds have a structure of Formula (III):

wherein

A is independently selected from

X₁, X₂, X₃, and X₄ are independently selected from H, deuterium, and D;

D is independently selected from

Z₁ is selected from C(CH₃)₂, C(Ph)₂, O, and N(Ph); and

Z₂ is independently selected from alkyl, aryl, and heteroaryl, and ispreferably selected from methyl, tert-butyl, phenyl, carbazolyl,phenylcarbazolyl, diphenylamino, and triphenylamino.

In some embodiments, A, is A1. In some embodiments, A, is A1. In someembodiments, A, is A2. In some embodiments, A, is A3. In someembodiments, A, is A4. In some embodiments, A, is A5.

In some embodiments, at least one of X₁, X₂, X₃, and X₄ is H. In someembodiments, least one of X₁, X₂, X₃, and X₄ is deuterium. In someembodiments, X₁, X₂, X₃, and X₄ are D. In some embodiments, one of X₁,X₂, X₃, and X₄ is D. In some embodiments, two of X₁, X₂, X₃, and X₄ areD. In some embodiments, three of X₁, X₂, X₃, and X₄ are D. In someembodiments, one of X₁, X₂, X₃, and X₄ is H. In some embodiments, two ofX₁, X₂, X₃, and X₄ are H. In some embodiments, one of X₁, X₂, X₃, and X₄is deuterium. In some embodiments, two of X₁, X₂, X₃, and X₄ aredeuterium.

In some embodiments, D is D1. In some embodiments, D is D2. In someembodiments, D is D3. In some embodiments, D is D4. In some embodiments,D is D5. In some embodiments, D is D6. In some embodiments, D is D7. Insome embodiments, D is selected from D1, D2, D3, D4, D5, D6, and D7. Insome embodiments, D is selected from D1, D2, and D3. In someembodiments, D is selected from D4, D5, D6, and D7.

In some embodiments, two instances of D are the same. In someembodiments, three instances of D are the same. In some embodiments,four instances of D are the same. In some embodiments, two instances ofD are different. In some embodiments, three instances of D aredifferent. In some embodiments, four instances of D are different.

In some embodiments, the compound of Formula (III) is selected from

9,9′-(2,5-bis(4,6-diphenylpyrimidin-2-yl)-1,3-phenylene)bis(9H-carbazole)9,9′-(2,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,3-phenylene)bis(9H-carbazole)9,9′-(2,5-bis(4,6-diphenylpyrimidin-2-yl)-1,3-phenylene)bis(3,6-dimethyl-9H-carbazole)9,9′-(2,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,3-phenylene)bis(3,6-dimethyl-9H-carbazole)9,9′-(3,6-bis(4,6-diphenylpyrimidin-2-yl)-1,2-phenylene)bis(9H-carbazole)9,9′-(3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,2-phenylene)bis(9H-carbazole)9,9′-(3,6-bis(2,6-diphenylpyridin-4-yl)-1,2-phenylene)bis(9H-carbazole)9,9′-(3,6-bis(2,6-diphenylpyrimidin-4-yl)-1,2-phenylene)bis(9H-carbazole)9,9′-(3,6-bis(4,6-diphenylpyrimidin-2-yl)-1,2-phenylene)bis(3,6-dimethyl-9H-carbazole)9,9′-(3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,2-phenylene)bis(3,6-dimethyl-9H-carbazole)9,9′-(3,6-bis(2,6-diphenylpyridin-4-yl)-1,2-phenylene)bis(3,6-dimethyl-9H-carbazole)9,9′-(3,6-bis(2,6-diphenylpyrimidin-4-yl)-1,2-phenylene)bis(3,6-dimethyl-9H-carbazole)9,9′-(2,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,4-phenylene)bis(9H-carbazole)9,9′-(2,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,4-phenylene)bis(3,6-dimethyl-9H-carbazole)9,9′-(2,5-bis(4,6-diphenylpyrimidin-2-yl)-1,4-phenylene)bis(9H-carbazole)9,9′-(2,5-bis(4,6-diphenylpyrimidin-2-yl)-1,4-phenylene)bis(3,6-dimethyl-9H-carbazole)9,9′,9″,9′″-(3,6-bis(4,6-diphenylpyrimidin-2-yl)benzene-1,2,4,5-tetrayl)tetrakis(9H-carbazole)9,9′,9″,9′″-(3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)benzene-1,2,4,5-tetrayl)tetrakis(9H-carbazole)9,9′-(4,6-di(9H-carbazol-9-yl)-2,5-bis(4,6-diphenylpyrimidin-2-yl)-1,3-phenylene)bis(3,6-dimethyl-9H-carbazole)4,6-di(9H-carbazol-9-yl)-2,5-bis(4,6-diphenylpyrimidin-2-yl)-N1,N1,N3,N3-tetraphenylbenzene-1,3-diamine9,9′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-1,4-phenylene)bis(3,6-dimethyl-9H-carbazole)2,5-bis(3,6-dimethyl-9H-carbazol-9-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-N1,N1,N4,N4-tetraphenylbenzene-1,4-diamine9,9′-(4,6-di(9H-carbazol-9-yl)-2,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,3-phenylene)bis(3,6-dimethyl-9H-carbazole)4,6-bis(3,6-dimethyl-9H-carbazol-9-yl)-2,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-N1,N1,N3,N3-tetraphenylbenzene-1,3-diamine2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-N1,N1,N4,N4-tetraphenylbenzene-1,4-diamine4,6-di(9H-carbazol-9-yl)-2,5-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-N1,N1,N3,N3-tetraphenylbenzene-1,3-diamine4,6-bis(3,6-dimethyl-9H-carbazol-9-yl)-2,5-bis(4,6-diphenylpyrimidin-2-yl)-N1,N1,N3,N3-tetraphenylbenzene-1,3-diamine2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-N1,N1,N4,N4-tetraphenylbenzene-1,4-diamine2,5-bis(3,6-dimethyl-9H-carbazol-9-yl)-3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-N1,N1,N4,N4-tetraphenylbenzene-1,4-diamine9,9′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,4-phenylene)bis(3,6-dimethyl-9H-carbazole)9,9′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-1,4-phenylene)bis(3,6-dimethyl-9H-carbazole)9,9′,9″,9′″-(3,6-bis(2,6-diphenylpyrimidin-4-yl)benzene-1,2,4,5-tetrayl)tetrakis(9H-carbazole)9,9′,9″,9′″-(3,6-bis(2,6-diphenylpyridin-4-yl)benzene-1,2,4,5-tetrayl)tetrakis(9H-carbazole)9,9′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-1,4-phenylene)bis(3,6-dimethyl-9H-carbazole)9,9′-(4,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-1,2-phenylene)bis(3,6-dimethyl-9H-carbazole)9,9′-(4,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-1,2-phenylene)bis(3,6-dimethyl-9H-carbazole)9,9′-(4,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,2-phenylene)bis(3,6-dimethyl-9H-carbazole)9,9′-(4,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-1,2-phenylene)bis(3,6-dimethyl-9H-carbazole)5,5′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-1,4-phenylene)bis(5H-benzo[b]carbazole)2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-N1,N1,N4,N4-tetra-p-tolylbenzene-1,4-diamine9,9′-(2,5-bis(dibenzo[b,d]thiophen-2-yl)-3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,4-phenylene)bis(9H-carbazole)9,9′-(2,5-bis(dibenzo[b,d]thiophen-2-yl)-3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,4-phenylene)bis(3,6-dimethyl-9H-carbazole)9,9′-(2,5-bis(dibenzo[b,d]thiophen-3-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-1,4-phenylene)bis(9H-carbazole)9,9′-(2,5-bis(dibenzo[b,d]thiophen-3-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-1,4-phenylene)bis(3,6-dimethyl-9H-carbazole)2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-N1,N4-diphenyl-N1,N4-di-p-tolylbenzene-1,4-diamine2,5-bis(3,6-dimethyl-9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-N1,N4-diphenyl-N1,N4-di-p-tolylbenzene-1,4-diamine2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-N1,N1,N4,N4-tetra-p-tolylbenzene-1,4-diamine9,9′-(2,5-bis(dibenzo[b,d]thiophen-4-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-1,4-phenylene)bis(9H-carbazole)9,9′-(2,5-bis(dibenzo[b,d]thiophen-4-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-1,4-phenylene)bis(3,6-dimethyl-9H-carbazole)9,9′-(2,5-bis(dibenzo[b,d]thiophen-4-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-1,4-phenylene)bis(9H-carbazole)9,9′-(2,5-bis(dibenzo[b,d]thiophen-4-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-1,4-phenylene)bis(3,6-dimethyl-9H-carbazole)10,10′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-1,4-phenylene)bis(10H-phenothiazine)9,9′-(2,5-bis(dibenzo[b,d]thiophen-1-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-1,4-phenylene)bis(3,6-dimethyl-9H-carbazole)10,10′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,4-phenylene)bis(9,9-dimethyl-9,10-dihydroacridine)10,10′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-1,4-phenylene)bis(10H-phenoxazine)10,10′-(2,5-bis(3,6-dimethyl-9H-carbazol-9-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-1,4-phenylene)bis(10H-phenoxazine)11,11′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-1,4-phenylene)bis(11H-benzo[a]carbazole)10,10′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-1,4-phenylene)bis(9,9-dimethyl-9,10-dihydroacridine)9,9′-(2,5-bis(dibenzo[b,d]thiophen-1-yl)-3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,4-phenylene)bis(9H-carbazole)9,9′-(2,5-bis(dibenzo[b,d]thiophen-1-yl)-3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,4-phenylene)bis(3,6-dimethyl-9H-carbazole)9,9′-(2,5-bis(dibenzo[b,d]thiophen-3-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-1,4-phenylene)bis(9H-carbazole)9,9′-(2,5-bis(dibenzo[b,d]thiophen-3-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-1,4-phenylene)bis(3,6-dimethyl-9H-carbazole)11,11′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-1,4-phenylene)bis(11H-benzo[a]carbazole)10,10′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-1,4-phenylene)bis(10H-phenothiazine)10,10′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-1,4-phenylene)bis(10H-phenoxazine)10,10′-(2,5-bis(3,6-dimethyl-9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-1,4-phenylene)bis(10H-phenoxazine)2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-N1,N4-diphenyl-N1,N4-di-p-tolylbenzene-1,4-diamine2,5-bis(3,6-dimethyl-9H-carbazol-9-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-N1,N4-diphenyl-N1,N4-di-p-tolylbenzene-1,4-diamine2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-N1,N4-diphenyl-N1,N4-di-m-tolylbenzene-1,4-diamine2,5-bis(3,6-dimethyl-9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-N1,N4-diphenyl-N1,N4-di-m-tolylbenzene-1,4-diamine7,7′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-1,4-phenylene)bis(7H-benzo[c]carbazole)5,5′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-1,4-phenylene)bis(5H-benzo[b]carbazole)9,9′-(2,5-bis(dibenzo[b,d]thiophen-1-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-1,4-phenylene)bis(3,6-dimethyl-9H-carbazole)9,9′-(2,5-bis(dibenzo[b,d]thiophen-4-yl)-3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,4-phenylene)bis(9H-carbazole)9,9′-(2,5-bis(dibenzo[b,d]thiophen-4-yl)-3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,4-phenylene)bis(3,6-dimethyl-9H-carbazole)2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-N1,N1,N4,N4-tetra-p-tolylbenzene-1,4-diamine2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-N1,N4-diphenyl-N1,N4-di-m-tolylbenzene-1,4-diamine2,5-bis(3,6-dimethyl-9H-carbazol-9-yl)-3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-N1,N4-diphenyl-N1,N4-di-m-tolylbenzene-1,4-diamine9,9′-(2,5-bis(dibenzo[b,d]thiophen-2-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-1,4-phenylene)bis(9H-carbazole)9,9′-(2,5-bis(dibenzo[b,d]thiophen-2-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-1,4-phenylene)bis(3,6-dimethyl-9H-carbazole)9,9′-(2,5-bis(dibenzo[b,d]thiophen-1-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-1,4-phenylene)bis(9H-carbazole)9,9′-(2,5-bis(dibenzo[b,d]thiophen-1-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-1,4-phenylene)bis(3,6-dimethyl-9H-carbazole)10,10′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,4-phenylene)bis(10H-phenoxazine)10,10′-(2,5-bis(3,6-dimethyl-9H-carbazol-9-yl)-3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,4-phenylene)bis(10H-phenoxazine)2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-N1,N4-bis(4-isopropylphenyl)-N1,N4-diphenylbenzene-1,4-diamine2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-N1,N4-diphenyl-N1,N4-di-m-tolylbenzene-1,4-diamine2,5-bis(3,6-dimethyl-9H-carbazol-9-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-N1,N4-diphenyl-N1,N4-di-m-tolylbenzene-1,4-diamine7,7′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-1,4-phenylene)bis(7H-benzo[c]carbazole)9,9′-(2,5-bis(dibenzo[b,d]thiophen-3-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-1,4-phenylene)bis(9H-carbazole)9,9′-(2,5-bis(dibenzo[b,d]thiophen-3-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-1,4-phenylene)bis(3,6-dimethyl-9H-carbazole)9,9′-(2,5-bis(dibenzo[b,d]thiophen-4-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-1,4-phenylene)bis(9H-carbazole)9,9′-(2,5-bis(dibenzo[b,d]thiophen-4-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-1,4-phenylene)bis(3,6-dimethyl-9H-carbazole)2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-N1,N4-diphenyl-N1,N4-di-m-tolylbenzene-1,4-diamine2,5-bis(3,6-dimethyl-9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-N1,N4-diphenyl-N1,N4-di-m-tolylbenzene-1,4-diamine10,10′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,4-phenylene)bis(10H-phenothiazine)10,10′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-1,4-phenylene)bis(9,9-dimethyl-9,10-dihydroacridine)2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-N1,N4-diphenyl-N1,N4-di-p-tolylbenzene-1,4-diamine2,5-bis(3,6-dimethyl-9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-N1,N4-diphenyl-N1,N4-di-p-tolylbenzene-1,4-diamine10,10′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-1,4-phenylene)bis(9,9-dimethyl-9,10-dihydroacridine)2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-N1,N1,N4,N4-tetraphenylbenzene-1,4-diamine2,5-bis(3,6-dimethyl-9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-N1,N1,N4,N4-tetraphenylbenzene-1,4-diamine9,9′-(2,5-bis(dibenzo[b,d]thiophen-2-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-1,4-phenylene)bis(9H-carbazole)9,9′-(2,5-bis(dibenzo[b,d]thiophen-2-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-1,4-phenylene)bis(3,6-dimethyl-9H-carbazole)2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-N1,N4-bis(4-isopropylphenyl)-N1,N4-diphenylbenzene-1,4-diamine2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-N1,N4-bis(4-isopropylphenyl)-N1,N4-diphenylbenzene-1,4-diamine10,10′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-1,4-phenylene)bis(10H-phenothiazine)2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-N1,N4-diphenyl-N1,N4-di-p-tolylbenzene-1,4-diamine2,5-bis(3,6-dimethyl-9H-carbazol-9-yl)-3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-N1,N4-diphenyl-N1,N4-di-p-tolylbenzene-1,4-diamine5,5′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-1,4-phenylene)bis(5H-benzo[b]carbazole)2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-N1,N4-bis(4-isopropylphenyl)-N1,N4-diphenylbenzene-1,4-diamine11,11′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-1,4-phenylene)bis(11H-benzo[a]carbazole)9,9′-(2,5-bis(dibenzo[b,d]thiophen-3-yl)-3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,4-phenylene)bis(9H-carbazole)9,9′-(2,5-bis(dibenzo[b,d]thiophen-3-yl)-3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,4-phenylene)bis(3,6-dimethyl-9H-carbazole)2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-N1,N1,N4,N4-tetraphenylbenzene-1,4-diamine2,5-bis(3,6-dimethyl-9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-N1,N1,N4,N4-tetraphenylbenzene-1,4-diamine2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-N1,N1,N4,N4-tetra-p-tolylbenzene-1,4-diamine10,10′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-1,4-phenylene)bis(10H-phenoxazine)10,10′-(2,5-bis(3,6-dimethyl-9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-1,4-phenylene)bis(10H-phenoxazine)9,9′-(2,5-bis(dibenzo[b,d]thiophen-2-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-1,4-phenylene)bis(9H-carbazole)9,9′-(2,5-bis(dibenzo[b,d]thiophen-2-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-1,4-phenylene)bis(3,6-dimethyl-9H-carbazole)7,7′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-1,4-phenylene)bis(7H-benzo[c]carbazole)2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-N1,N4-diphenylbenzene-1,4-diamine2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-N1,N4-diphenylbenzene-1,4-diamine2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)benzene-1,4-diamine2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)benzene-1,4-diamine2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-N1,N4-diphenylbenzene-1,4-diamine2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)benzene-1,4-diamine2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-N1,N4-diphenylbenzene-1,4-diamine2,5-bis(3,6-dimethyl-9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-N1,N4-diphenylbenzene-1,4-diamine2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)benzene-1,4-diamine2,5-bis(3,6-dimethyl-9H-carbazol-9-yl)-3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-N1,N4-diphenylbenzene-1,4-diamine2,5-bis(3,6-dimethyl-9H-carbazol-9-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-N1,N4-diphenylbenzene-1,4-diamine10,10′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenylpyrimidin-2-yl)-1,4-phenylene)bis(9,10-dihydroacridine)2,5-bis(3,6-dimethyl-9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-N1,N4-diphenylbenzene-1,4-diamine10,10′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyridin-4-yl)-1,4-phenylene)bis(9,10-dihydroacridine)10,10′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(2,6-diphenylpyrimidin-4-yl)-1,4-phenylene)bis(9,10-dihydroacridine)10,10′-(2,5-di(9H-carbazol-9-yl)-3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,4-phenylene)bis(9,10-dihydroacridine)9,9′,9″,9′″-(3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)benzene-1,2,4,5-tetrayl)tetrakis(1-methyl-9H-carbazole); and9,9′,9″,9′″-(3,6-bis(4,6-diphenylpyrimidin-2-yl)benzene-1,2,4,5-tetrayl)tetrakis(1-methyl-9H-carbazole)

In some embodiments, compounds of Formula (III) are selected from

In some embodiments, the compounds have a structure of Formula (IV):

wherein

X is C(R₆);

R₁, R₂, R₃, R₄, R₅, and R₆ are independently selected from the groupconsisting of A, D, H, deuterium, and Ph;

at least two of R₁, R₂, R₃, R₄, R₅, and R₆ is A;

at least one of R₁, R₂, R₃, R₄, R₅, and R₆ is D;

A is

D is

Y is C(H) or N;

at least one of Y is N;

Z is H, Me, or Ph.

In some embodiments, D is D1. In some embodiments, D is D2. In someembodiments, D is D3.

In some embodiments, Y is C(H). In some embodiments, Y is N.

In some embodiments, Z is H. In some embodiments, Z is Me. In someembodiments, Z is Ph.

In some embodiments, only one A is present. In some embodiments, atleast one instance of A is present. In some embodiments, at least twoinstances of A are present. In some embodiments, as least threeinstances of A are present. In some embodiments, at least four instancesof A are present.

In some embodiments, only one instance of D is present. In someembodiments, at least one instance of D is present. In some embodiments,at least two instances of D are present. In some embodiments, as leastthree instances of D are present. In some embodiments, at least fourinstances of D are present.

In some embodiments, only one instance of A and only one instance of Dare present. In some embodiments, two instances of A and two instancesof D are present. In some embodiments, two A and three D are present. Insome embodiments, three instances of A and two instances of D arepresent. In some embodiments, three instances of A and three instancesof D are present. In some embodiments, two instances of A and threeinstances of D are present. In some embodiments, four instances of A andtwo instances of D are present. In some embodiments, two instances of Aand four instances of D are present.

In some embodiments, at least one of R₁, R₂, R₃, R₄, R₅, and R₆ is H. Insome embodiments, at least one of R₁, R₂, R₃, R₄, R₅, and R₆ is Ph. Insome embodiments, at least one of R₁, R₂, R₃, R₄, R₅, and R₆ is H andone is Ph.

In some embodiments the compound of Formula (IV) is selected from:3,3′,3″-(2,4-bis(4,6-diphenylpyrimidin-2-yl)benzene-1,3,5-triyl)tris(9-phenyl-9H-carbazole);

-   3,3′-(5′,6′-bis(4,6-diphenylpyrimidin-2-yl)-[1,1′:3′,1″-terphenyl]-2′,4′-diyl)bis(9-phenyl-9H-carbazole);-   3,3′-(3,4-bis(4,6-diphenylpyrimidin-2-yl)-1,2-phenylene)bis(9-phenyl-9H-carbazole);-   9-phenyl-3-(2′,4′,6′-tris(4,6-diphenylpyrimidin-2-yl)-[1,1′:3′,1″-terphenyl]-5′-yl)-9H-carbazole;-   3,3′-(4′,5′-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-[1,1′:2′,1″-terphenyl]-3′,6′-diyl)bis(9-phenyl-9H-carbazole);-   2,2′-(2,3-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,4-phenylene)bis(9-phenyl-9H-carbazole);-   3,3′,3″,3′″-(3-(4,6-diphenyl-1,3,5-triazin-2-yl)benzene-1,2,4,5-tetrayl)tetrakis(9-phenyl-9H-carbazole);-   3,3′-(5′,6′-bis(4,6-diphenylpyrimidin-2-yl)-[1,1′:2′,1″-terphenyl]-3′,4′-diyl)bis(9-phenyl-9H-carbazole);-   3,3′-(3′,6′-bis(4,6-diphenylpyrimidin-2-yl)-[1,1′:2′,1″-terphenyl]-4′,5′-diyl)bis(9-phenyl-9H-carbazole);-   3,3′-(3,5-di(9H-carbazol-9-yl)-4-(4,6-diphenyl-1,3,5-triazin-2-yl)-[1,1′-biphenyl]-2,6-diyl)bis(9-phenyl-91H-carbazole);-   3,3′,3″-(5′-(4,6-diphenyl-1,3,5-triazin-2-yl)-[1,1′:3′,1″-terphenyl]-2′,4′,6′-triyl)tris(9-phenyl-9H-carbazole);-   9,9′-(5′-(2,6-diphenylpyrimidin-4-yl)-2′-(9-phenyl-9H-carbazol-2-yl)-[1,1′:3′,1″-terphenyl]-4′,6′-diyl)bis(3,6-dimethyl-9H-carbazole);-   9-phenyl-3-(2,4,6-tris(4,6-diphenylpyrimidin-2-yl)phenyl)-9H-carbazole;-   3,3′-(2,4,6-tris(4,6-diphenylpyrimidin-2-yl)-1,3-phenylene)bis(9-phenyl-9H-carbazole);-   2,2′-(3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,2-phenylene)bis(9-phenyl-9H-carbazole);-   3,3′-(3,6-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-1,2-phenylene)bis(9-phenyl-9H-carbazole);-   3,3′-(3′,5′-bis(4,6-diphenyl-1,3,5-triazin-2-yl)-[1,1′:4′,1″-terphenyl]-2′,6′-diyl)bis(9-phenyl-9H-carbazole);    and-   9,9′-(4-(4,6-diphenyl-1,3,5-triazin-2-yl)-2,6-bis(9-phenyl-9H-carbazol-2-yl)-[1,1′-biphenyl]-3,5-diyl)bis(3,6-dimethyl-9H-carbazole).

In some embodiments the compound of Formula (IV) is selected from:

In some embodiments, compounds of formula (I) is:

In some embodiments, compounds of formula (I) is:

In some embodiments compounds of formula (I) is:

In some embodiments, compounds of formula (I) is:

In some embodiments, compounds of formula (I) is:

In some embodiments, compounds of formula (I), (II), (III), or (IV) aresubstituted with deuterium.

In some embodiments, compounds of formula (I), (II), (III), or (IV) arelight-emitting materials.

In some embodiments, compounds of formula (I), (II), (III), or (IV) arecompound capable of emitting delayed fluorescence.

In some embodiments of the present disclosure, when excited via thermalor electronic means, the compounds of formula (I), (II), (III), or (IV)can produce light in the blue, green, yellow, orange, or red region ofthe visible spectrum (e.g., about 420 nm to about 500 nm, about 500 nmto about 600 nm, or about 600 nm to about 700 nm).

In some embodiments of the present disclosure, when excited via thermalor electronic means, the compounds of formula (I), (II), (III), or (IV)can produce light in the red or orange region of the visible spectrum(e.g., about 620 nm to about 780 nm; about 650 nm).

In some embodiments of the present disclosure, when excited via thermalor electronic means, the compounds of formula (I), (II), (III), or (IV)can produce light in the orange or yellow region of the visible spectrum(e.g., about 570 nm to about 620 nm; about 590 nm; about 570 nm).

In some embodiments of the present disclosure, when excited via thermalor electronic means, the compounds of formula (I), (II), (III), or (IV)can produce light in the green region of the visible spectrum (e.g.,about 490 nm to about 575 nm; about 510 nm).

In some embodiments of the present disclosure, when excited via thermalor electronic means, the compounds of formula (I), (II), (III), or (IV)can produce light in the blue region of the visible spectrum (e.g.,about 400 nm to about 490 nm; about 475 nm).

Electronic properties of a library of small chemical molecules can becomputed using known ab initio quantum mechanical computations. Forexample, using a time-dependent density functional theory using, as abasis set, the set of functions known as 6-31G* and a Becke,3-parameter, Lee-Yang-Parr hybrid functional to solve Hartree-Fockequations (TD-DFT/B3LYP/6-31G*), molecular fragments (moieties) can bescreened which have HOMOs above a specific threshold and LUMOs below aspecific threshold, and wherein the calculated triplet state of themoieties is above 2.75 eV.

Therefore, for example, a donor moiety (“D”) can be selected because ithas a HOMO energy (e.g., an ionization potential) of greater than orequal to −6.5 eV. An acceptor moiety (“A”) can be selected because ithas, for example, a LUMO energy (e.g., an electron affinity) of lessthan or equal to −0.5 eV. The bridge moiety (“B”) can be a rigidconjugated system which can, for example, sterically restrict theacceptor and donor moieties into a specific configuration, therebypreventing the overlap between the conjugated π system of donor andacceptor moieties.

In some embodiments, the compound library is filtered using one or moreof the following properties:

-   -   1. emission near a certain wavelength;    -   2. calculated triplet state above a certain energy level;    -   3. ΔEST value below a certain value;    -   4. quantum yield above a certain value;    -   5. HOMO level; and    -   6. LUMO level.

In some embodiments, the difference between the lowest singlet excitedstate and the lowest triplet excited state at 77K (ΔEST) is less thanabout 0.5 eV, less than about 0.4 eV, less than about 0.3 eV, less thanabout 0.2 eV, or less than about 0.1 eV. In some embodiments, the ΔESTvalue is less than about 0.09 eV, less than about 0.08 eV, less thanabout 0.07 eV, less than about 0.06 eV, less than about 0.05 eV, lessthan about 0.04 eV, less than about 0.03 eV, less than about 0.02 eV, orless than about 0.01 eV.

In some embodiments, a compound of formula (I), (II), (III), or (IV)exhibits an external quantum yield of greater than 25%, such as about30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%,about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about95%, or greater.

Compositions with the Disclosed Compounds

In some embodiments, a compound of formula (I), (II), (III), or (IV) iscombined with, dispersed within, covalently bonded to, coated with,formed on, or otherwise associated with, one or more materials (e.g.,small molecules, polymers, metals, metal complexes, etc.) to form a filmor layer in solid state. For example, the compound of formula (I), (II),(III), or (IV) may be combined with an electroactive material to form afilm. In some cases, the compound of formula (I), (II), (III), or (IV)may be combined with a hole-transport polymer. In some cases, thecompound of formula (I), (II), (III), or (IV) may be combined with anelectron-transport polymer. In some cases, the compound of formula (I),(II), (III), or (IV) may be combined with a hole-transport polymer andan electron-transport polymer. In some cases, the compound of formula(I), (II), (III), or (IV) may be combined with a copolymer comprisingboth hole-transport portions and electron-transport portions. In suchembodiments, electrons and/or holes formed within the solid film orlayer may interact with the compound of formula (I), (II), (III), or(IV)

Exemplary Uses of the Disclosed Compounds

In some embodiments, a compound of formula (I), (II), (III), or (IV) iscombined with, dispersed within, covalently bonded to, coated with,formed on, or otherwise associated with, one or more materials (e.g.,small molecules, polymers, metals, metal complexes, etc.) to form a filmor layer in solid state. For example, the compound of formula (I), (II),(III), or (IV) may be combined with an electroactive material to form afilm. In some cases, the compound of formula (I), (II), (III), or (IV)may be combined with a hole-transport polymer. In some cases, thecompound of formula (I), (II), (III), or (IV) may be combined with anelectron-transport polymer. In some cases, the compound of formula (I),(II), (III), or (IV) may be combined with a hole-transport polymer andan electron-transport polymer. In some cases, the compound of formula(I), (II), (III), or (IV) may be combined with a copolymer comprisingboth hole-transport portions and electron-transport portions. In suchembodiments, electrons and/or holes formed within the solid film orlayer may interact with the compound of formula (I), (II), (III), or(IV).

Exemplary Uses of the Disclosed Compounds

Organic Light-Emitting Diodes

One aspect of the invention relates to use of the compound of formula(I), (II), (III), or (IV) of the invention as a light-emitting materialof an organic light-emitting device. In some embodiments, the compoundrepresented by the formula (I), (II), (III), or (IV) of the inventionmay be effectively used as a light-emitting material in a light-emittinglayer of an organic light-emitting device. In some embodiments, thecompound of formula (I), (II), (III), or (IV) comprises a delayedfluorescent material emitting delayed fluorescent light (delayedfluorescence emitter). In some embodiments, the invention provides adelayed fluorescence emitter having the structure of formula (I), (II),(III), or (IV). In some embodiments, the invention relates to the use ofthe compound of formula (I), (II), (III), or (IV) as the delayedfluorescence emitter. In some embodiments, the invention relates to amethod for emitting delayed fluorescent light from the compound offormula (I), (II), (III), or (IV). In some embodiments, an organiclight-emitting device comprising the compound as a light-emittingmaterial, emits delayed fluorescent light, and has a high light emissionefficiency.

In some embodiments, a light-emitting layer comprises a compound offormula (I), wherein the compound of formula (I), (II), (III), or (IV)is oriented parallel to the substrate. In some embodiments, thesubstrate is a film forming surface. In some embodiments, theorientation of the compound of formula (I), (II), (III), or (IV) withrespect to the film forming surface influences or determines thepropagation directions of the light emitted by the compound to bealigned. In some embodiments, the alignment of the propagationdirections of the light emitted by the compound of formula (I), (II),(III), or (IV) enhances the light extraction efficiency from thelight-emitting layer.

One aspect of the invention relates to an organic light-emitting device.In some embodiments, the organic light-emitting device comprises alight-emitting layer. In some embodiments, the light-emitting layercomprises a compound of formula (I), (II), (III), or (IV) as alight-emitting material. In some embodiments, the organic light-emittingdevice is an organic photoluminescent device (organic PL device). Insome embodiments, the organic light-emitting device is an organicelectroluminescent device (organic EL device). In some embodiments, thecompound of formula (I), (II), (III), or (IV) assists the light emissionof another light-emitting material comprised in the light-emittinglayer, i.e., as a so-called assistant dopant. In some embodiments, thecompound of formula (I), (II), (III), or (IV) comprised in thelight-emitting layer is in its the lowest excited singlet energy level,which is comprised between the lowest excited singlet energy level ofthe host material comprised in the light-emitting layer and the lowestexcited singlet energy level of the another light-emitting materialcomprised in the light-emitting layer.

In some embodiments, the organic photoluminescent device comprises atleast one light-emitting layer. In some embodiments, the organicelectroluminescent device comprises at least an anode, a cathode, and anorganic layer between the anode and the cathode. In some embodiments,the organic layer comprises at least a light-emitting layer. In someembodiments, the organic layer comprises only a light-emitting layer. Insome embodiments, the organic layer, comprises one or more organiclayers in addition to the light-emitting layer. Examples of the organiclayer include a hole transporting layer, a hole injection layer, anelectron barrier layer, a hole barrier layer, an electron injectionlayer, an electron transporting layer and an exciton barrier layer. Insome embodiments, the hole transporting layer may be a hole injectionand transporting layer having a hole injection function, and theelectron transporting layer may be an electron injection andtransporting layer having an electron injection function. An example ofan organic electroluminescent device is shown in the FIGURE.

Substrate

In some embodiments, the organic electroluminescent device of theinvention is supported by a substrate, wherein the substrate is notparticularly limited and may be any of those that have been commonlyused in an organic electroluminescent device, for example those formedof glass, transparent plastics, quartz and silicon.

Anode

In some embodiments, the anode of the organic electroluminescent deviceis made of a metal, an alloy, an electroconductive compound, or acombination thereof. In some embodiments, the metal, alloy, orelectroconductive compound has a large work function (4 eV or more). Insome embodiments, the metal is Au. In some embodiments, theelectroconductive transparent material is selected from CuI, indium tinoxide (ITO), SnO₂, and ZnO. In some embodiments, an amorphous materialcapable of forming a transparent electroconductive film, such as IDIXO(In₂O₃—ZnO), is be used. In some embodiments, the anode is a thin film.In some embodiments the thin film is made by vapor deposition orsputtering. In some embodiments, the film is patterned by aphotolithography method. In some embodiments, where the pattern may notrequire high accuracy (for example, approximately 100 μm or more), thepattern may be formed with a mask having a desired shape on vapordeposition or sputtering of the electrode material. In some embodiments,when a material can be applied as a coating, such as an organicelectroconductive compound, a wet film forming method, such as aprinting method and a coating method is used. In some embodiments, whenthe emitted light goes through the anode, the anode has a transmittanceof more than 10%, and the anode has a sheet resistance of severalhundred Ohm per square or less. In some embodiments, the thickness ofthe anode is from 10 to 1,000 nm. In some embodiments, the thickness ofthe anode is from 10 to 200 nm. In some embodiments, the thickness ofthe anode varies depending on the material used.

Cathode

In some embodiments, the cathode is made of an electrode material ametal having a small work function (4 eV or less) (referred to as anelectron injection metal), an alloy, an electroconductive compound, or acombination thereof. In some embodiments, the electrode material isselected from sodium, a sodium-potassium alloy, magnesium, lithium, amagnesium-cupper mixture, a magnesium-silver mixture, amagnesium-aluminum mixture, a magnesium-indium mixture, analuminum-aluminum oxide (Al₂O₃) mixture, indium, a lithium-aluminummixture, and a rare earth metal. In some embodiments, a mixture of anelectron injection metal and a second metal that is a stable metalhaving a larger work function than the electron injection metal is used.In some embodiments, the mixture is selected from a magnesium-silvermixture, a magnesium-aluminum mixture, a magnesium-indium mixture, analuminum-aluminum oxide (Al₂O₃) mixture, a lithium-aluminum mixture, andaluminium. In some embodiments, the mixture increases the electroninjection property and the durability against oxidation. In someembodiments, the cathode is produced by forming the electrode materialinto a thin film by vapor deposition or sputtering. In some embodiments,the cathode has a sheet resistance of several hundred Ohm per square orless. In some embodiments, the thickness of the cathode ranges from 10nm to 5 m. In some embodiments, the thickness of the cathode ranges from50 to 200 nm. In some embodiments, for transmitting the emitted light,any one of the anode and the cathode of the organic electroluminescentdevice is transparent or translucent. In some embodiments, thetransparent or translucent electroluminescent devices enhances the lightemission luminance.

In some embodiments, the cathode is formed with an electroconductivetransparent material, as described for the anode, to form a transparentor translucent cathode. In some embodiments, a device comprises an anodeand a cathode, both being transparent or translucent.

Light-Emitting Layer

In some embodiments, the light-emitting layer is a layer, in which holesand electrons, injected respectively from the anode and the cathode, arerecombined to form excitons. In some embodiments the layer emits light.

In some embodiments, a light-emitting material is solely used as thelight-emitting layer. In some embodiments, the light-emitting layercontains a light-emitting material, and a host material. In someembodiments, the light-emitting material is one or more compounds offormula (I), (II), (III), or (IV). In some embodiments, for the organicelectroluminescent device and the organic photoluminescent device toexhibit a high light emission efficiency, the singlet excitons and thetriplet excitons generated in the light-emitting material are confinedin the light-emitting material. In some embodiments, a host material isused in addition to the light-emitting material in the light-emittinglayer. In some embodiments, the host material is an organic compound. Insome embodiments, the organic compounds has excited singlet energy andexcited triplet energy, at least one of which is higher than those ofthe light-emitting material of the invention. In some embodiments, thesinglet excitons and the triplet excitons generated in thelight-emitting material of the invention are confined in the moleculesof the light-emitting material of the invention. In some embodiments,the singlet and triplet excitons are sufficient confined to elicit thelight emission efficiency. In some embodiments, the singlet excitons andthe triplet excitons are not confined sufficiently, though a high lightemission efficiency is still obtained, and thus a host material capableof achieving a high light emission efficiency can be used in theinvention without any particular limitation. In some embodiments, thelight emission occurs in the light-emitting material of thelight-emitting layer in the devices of the invention. In someembodiments, the emitted light contains both fluorescent light anddelayed fluorescent light. In some embodiments, the emitted lightcomprises emitted light from the host material. In some embodiments, theemitted light consists of emitted light from the host material. In someembodiments, the emitted light light comprises emitted light from acompound of formula (I), (II), (III), or (IV), and emitted light fromthe host material. In some embodiments, a TADF molecule and a hostmaterial are used. In some embodiments, the TADF will be assistantdopant.

In some embodiments, when a host material is used, the amount of thecompound of the invention as the light-emitting material contained inthe light-emitting layer is 0.1% by weight or more. In some embodiments,when a host material is used, the amount of the compound of theinvention as the light-emitting material contained in the light-emittinglayer is 1% by weight or more. In some embodiments, when a host materialis used, the amount of the compound of the invention as thelight-emitting material contained in the light-emitting layer is 50% byweight or less. In some embodiments, when a host material is used, theamount of the compound of the invention as the light-emitting materialcontained in the light-emitting layer is 20% by weight or less. In someembodiments, when a host material is used, the amount of the compound ofthe invention as the light-emitting material contained in thelight-emitting layer is 10% by weight or less.

In some embodiments, the host material in the light-emitting layer is anorganic compound comprising a hole transporting function and an electrontransporting function. In some embodiments, the host material in thelight-emitting layer is an organic compound that prevents the emittedlight from being increased in wavelength. In some embodiments, the hostmaterial in the light-emitting layer is an organic compound with a highglass transition temperature.

Injection Layer

An injection layer is a layer between the electrode and the organiclayer. In some embodiments, the injection layer decreases the drivingvoltage and enhances the light emission luminance. In some embodimentsthe injection layer includes a hole injection layer and an electroninjection layer. The injection layer can be positioned between the anodeand the light-emitting layer or the hole transporting layer, and betweenthe cathode and the light-emitting layer or the electron transportinglayer. In some embodiments, an injection layer is present. In someembodiments, no injection layer is present.

Barrier Layer

A barrier layer is a layer capable of inhibiting charges (electrons orholes) and/or excitons present in the light-emitting layer from beingdiffused outside the light-emitting layer. In some embodiments, theelectron barrier layer is between the light-emitting layer and the holetransporting layer, and inhibits electrons from passing through thelight-emitting layer toward the hole transporting layer. In someembodiments, the hole barrier layer is between the light-emitting layerand the electron transporting layer, and inhibits holes from passingthrough the light-emitting layer toward the electron transporting layer.In some embodiments, the barrier layer inhibits excitons from beingdiffused outside the light-emitting layer. In some embodiments, theelectron barrier layer and the hole barrier layer are exciton barrierlayers. As used herein, the term “electron barrier layer” or “excitonbarrier layer” includes a layer that has the functions of both electronbarrier layer and of an exciton barrier layer.

Hole Barrier Layer

A hole barrier layer acts as an electron transporting layer. In someembodiments, the hole barrier layer inhibits holes from reaching theelectron transporting layer while transporting electrons. In someembodiments, the hole barrier layer enhances the recombinationprobability of electrons and holes in the light-emitting layer. Thematerial for the hole barrier layer may be the same materials as theones described for the electron transporting layer.

Electron Barrier Layer

As electron barrier layer transports holes. In some embodiments, theelectron barrier layer inhibits electrons from reaching the holetransporting layer while transporting holes. In some embodiments, theelectron barrier layer enhances the recombination probability ofelectrons and holes in the light-emitting layer.

Exciton Barrier Layer

An exciton barrier layer inhibits excitons generated throughrecombination of holes and electrons in the light-emitting layer frombeing diffused to the charge transporting layer. In some embodiments,the exciton barrier layer enables effective confinement of excitons inthe light-emitting layer. In some embodiments, the light emissionefficiency of the device is enhanced. In some embodiments, the excitonbarrier layer is adjacent to the light-emitting layer on any of the sideof the anode and the side of the cathode, and on both the sides. In someembodiments, where the exciton barrier layer is on the side of theanode, the layer can be between the hole transporting layer and thelight-emitting layer and adjacent to the light-emitting layer. In someembodiments, where the exciton barrier layer is on the side of thecathode, the layer can be between the light-emitting layer and thecathode and adjacent to the light-emitting layer. In some embodiments, ahole injection layer, an electron barrier layer, or a similar layer isbetween the anode and the exciton barrier layer that is adjacent to thelight-emitting layer on the side of the anode. In some embodiments, ahole injection layer, an electron barrier layer, a hole barrier layer,or a similar layer is between the cathode and the exciton barrier layerthat is adjacent to the light-emitting layer on the side of the cathode.In some embodiments, the exciton barrier layer comprises excited singletenergy and excited triplet energy, at least one of which is higher thanthe excited singlet energy and the excited triplet energy of thelight-emitting material, respectively.

Hole Transporting Layer

The hole transporting layer comprises a hole transporting material. Insome embodiments, the hole transporting layer is a single layer. In someembodiments, the hole transporting layer comprises a plurality oflayers.

In some embodiments, the hole transporting material has one of injectionor transporting property of holes and barrier property of electrons. Insome embodiments, the hole transporting material is an organic material.In some embodiments, the hole transporting material is an inorganicmaterial. Examples of known hole transporting materials that may be usedherein include but are not limited to a triazole derivative, anoxadiazole derivative, an imidazole derivative, a carbazole derivative,an indolocarbazole derivative, a polyarylalkane derivative, a pyrazolinederivative, a pyrazolone derivative, a phenylenediamine derivative, anarylamine derivative, an amino-substituted chalcone derivative, anoxazole derivative, a styrylanthracene derivative, a fluorenonederivative, a hydrazone derivative, a stilbene derivative, a silazanederivative, an aniline copolymer and an electroconductive polymeroligomer, particularly a thiophene oligomer, or a combination thereof.In some embodiments, the hole transporting material is selected from aporphyrin compound, an aromatic tertiary amine compound, and astyrylamine compound. In some embodiments, the hole transportingmaterial is an aromatic tertiary amine compound.

Electron Transporting Layer

The electron transporting layer comprises an electron transportingmaterial. In some embodiments, the electron transporting layer is asingle layer. In some embodiments, the electron transporting layercomprises a plurality of layer.

In some embodiments, the electron transporting material needs only tohave a function of transporting electrons, which are injected from thecathode, to the light-emitting layer. In some embodiments, the electrontransporting material also function as a hole barrier material. Examplesof the electron transporting layer that may be used herein include butare not limited to a nitro-substituted fluorene derivative, adiphenylquinone derivative, a thiopyran dioxide derivative,carbodiimide, a fluorenylidene methane derivative, anthraquinodimethane,an anthrone derivatives, an oxadiazole derivative, an azole derivative,an azine derivative, or a combination thereof, or a polymer thereof. Insome embodiments, the electron transporting material is a thiadiazolederivative, or a quinoxaline derivative. In some embodiments, theelectron transporting material is a polymer material.

In some embodiments, a compound of formula (I), (II), (III), or (IV) iscomprised in the light-emitting layer of a device of the invention. Insome embodiments, a compound of formula (I), (II), (III), or (IV) iscomprised in the light-emitting layer and at least one other layers. Insome embodiments, the compounds of formula (I), (II), (III), or (IV) areindependently selected for each layers. In some embodiments, thecompounds of formula (I), (II), (III), or (IV) are the same. In someembodiments, the compounds of formula (I), (II), (III), or (IV) aredifferent. For example, the compound represented by the formula (I),(II), (III), or (IV) may be used in the injection layer, the barrierlayer, the hole barrier layer, the electron barrier layer, the excitonbarrier layer, the hole transporting layer, the electron transportinglayer and the like described above. The film forming method of thelayers are not particularly limited, and the layers may be produced byany of a dry process and a wet process.

Specific examples of materials that can be used in the organicelectroluminescent device are shown below, but the materials that may beused in the invention are not construed as being limited to the examplecompounds. In some embodiments, a material having a particular functioncan also have another function.

In some embodiments, the host material is selected from the groupconsisting of:

Devices

In some embodiments, the compounds of the disclosure are incorporatedinto a device. For example, the device includes, but is not limited toan OLED bulb, an OLED lamp, a television screen, a computer monitor, amobile phone, and a tablet.

In some embodiments, an electronic device comprises an OLED comprisingan anode, a cathode, and at least one organic layer comprising alight-emitting layer between the anode and the cathode, wherein thelight-emitting layer comprises

a host material; and

a compound of Formula (I), (II), (III), or (IV).

In some embodiments, the light-emitting layer of the OLED furthercomprises a fluorescent material wherein the compound of formula (I),(II), (III), or (IV) converts triplets to singlets for the fluorescentemitter.

In some embodiments, compositions described herein may be incorporatedinto various light-sensitive or light-activated devices, such as a OLEDsor photovoltaic devices. In some embodiments, the composition may beuseful in facilitating charge transfer or energy transfer within adevice and/or as a hole-transport material. The device may be, forexample, an organic light-emitting diode (OLED), an organic integratedcircuit (O-IC), an organic field-effect transistor (O-FET), an organicthin-film transistor (O-TFT), an organic light-emitting transistor(O-LET), an organic solar cell (O-SC), an organic optical detector, anorganic photoreceptor, an organic field-quench device (O-FQD), alight-emitting electrochemical cell (LEC) or an organic laser diode(O-laser).

Bulbs or Lamps

In some embodiments, an electronic device comprises an OLED comprisingan anode, a cathode, and at least one organic layer comprising alight-emitting layer between the anode and the cathode, wherein thelight-emitting layer comprises

a host material;

a compound of formula (I), (II), (III), or (IV);

wherein the compound of formula (I), (II), (III), or (IV) is alight-emitting material; and

an OLED driver circuit.

In some embodiments, a device comprises OLEDs that differ in color. Insome embodiments, a device comprises an array comprising a combinationof OLEDs. In some embodiments, the combination of OLEDs is a combinationof three colors (e.g., RGB). In some embodiments, the combination ofOLEDs is a combination of colors that are not red, green, or blue (forexample, orange and yellow green). In some embodiments, the combinationof OLEDs is a combination of two, four, or more colors.

In some embodiments, a device is an OLED light comprising:

a circuit board having a first side with a mounting surface and anopposing second side, and defining at least one aperture;

at least one OLED on the mounting surface, the at least one OLEDconfigured to emanate light, comprising:

-   -   an anode, a cathode, and at least one organic layer comprising a        light-emitting layer between the anode and the cathode, wherein        the light-emitting layer comprises    -   a host material; and    -   a compound of formula (I), (II), (III), or (IV);    -   wherein the compound of formula (I), (II), (III), or (IV) is a        light-emitting material;

a housing for the circuit board; and

at least one connector arranged at an end of the housing, the housingand the connector defining a package adapted for installation in a lightfixture.

In some embodiments, the OLED light comprises a plurality of OLEDsmounted on a circuit board such that light emanates in a plurality ofdirections. In some embodiments, a portion of the light emanated in afirst direction is deflected to emanate in a second direction. In someembodiments, a reflector is used to deflect the light emanated in afirst direction.

Displays or Screens

In some embodiments, the compounds of formula (I), (II), (III), or (IV)can be used in a screen or a display. In some embodiments, the compoundsof formula (I), (II), (III), or (IV) are deposited onto a substrateusing a process including, but not limited to, vacuum evaporation,deposition, vapor deposition, or chemical vapor deposition (CVD). Insome embodiments, the substrate is a photoplate structure useful in atwo-sided etch provides a unique aspect ratio pixel. The screen (whichmay also be referred to as a mask) is used in a process in themanufacturing of OLED displays. The corresponding artwork pattern designfacilitates a very steep and narrow tie-bar between the pixels in thevertical direction and a large, sweeping bevel opening in the horizontaldirection. This allows the close patterning of pixels needed for highdefinition displays while optimizing the chemical deposition onto a TFTbackplane.

The internal patterning of the pixel allows the construction of a3-dimensional pixel opening with varying aspect ratios in the horizontaland vertical directions. Additionally, the use of imaged “stripes” orhalftone circles within the pixel area inhibits etching in specificareas until these specific patterns are undercut and fall off thesubstrate. At that point the entire pixel area is subjected to a similaretch rate but the depths are varying depending on the halftone pattern.Varying the size and spacing of the halftone pattern allows etching tobe inhibited at different rates within the pixel allowing for alocalized deeper etch needed to create steep vertical bevels.

A preferred material for the deposition mask is invar. Invar is a metalalloy that is cold rolled into long thin sheet in a steel mill. Invarcannot be electrodeposited onto a rotating mandrel as the nickel mask. Apreferred and more cost feasible method for forming the open areas inthe mask used for deposition is through a wet chemical etching.

In some embodiments, a screen or display pattern is a pixel matrix on asubstrate. In some embodiments, a screen or display pattern isfabricated using lithography (e.g., photolithography and e-beamlithography). In some embodiments, a screen or display pattern isfabricated using a wet chemical etch. In further embodiments, a screenor display pattern is fabricated using plasma etching.

Methods of Manufacturing Devices Using the Disclosed Compounds

An OLED display is generally manufactured by forming a large motherpanel and then cutting the mother panel in units of cell panels. Ingeneral, each of the cell panels on the mother panel is formed byforming a thin film transistor (TFT) including an active layer and asource/drain electrode on a base substrate, applying a planarizationfilm to the TFT, and sequentially forming a pixel electrode, alight-emitting layer, a counter electrode, and an encapsulation layer,and then is cut from the mother panel.

An OLED display is generally manufactured by forming a large motherpanel and then cutting the mother panel in units of cell panels. Ingeneral, each of the cell panels on the mother panel is formed byforming a thin film transistor (TFT) including an active layer and asource/drain electrode on a base substrate, applying a planarizationfilm to the TFT, and sequentially forming a pixel electrode, alight-emitting layer, a counter electrode, and an encapsulation layer,and then is cut from the mother panel.

In another aspect, provided herein is a method of manufacturing anorganic light-emitting diode (OLED) display, the method comprising:

forming a barrier layer on a base substrate of a mother panel;

forming a plurality of display units in units of cell panels on thebarrier layer;

forming an encapsulation layer on each of the display units of the cellpanels;

applying an organic film to an interface portion between the cellpanels.

In some embodiments, the barrier layer is an inorganic film formed of,for example, SiNx, and an edge portion of the barrier layer is coveredwith an organic film formed of polyimide or acryl. In some embodiments,the organic film helps the mother panel to be softly cut in units of thecell panel.

In some embodiments, the thin film transistor (TFT) layer includes alight-emitting layer, a gate electrode, and a source/drain electrode.Each of the plurality of display units may include a thin filmtransistor (TFT) layer, a planarization film formed on the TFT layer,and a light-emitting unit formed on the planarization film, wherein theorganic film applied to the interface portion is formed of a samematerial as a material of the planarization film and is formed at a sametime as the planarization film is formed. In some embodiments, alight-emitting unit is connected to the TFT layer with a passivationlayer and a planarization film therebetween and an encapsulation layerthat covers and protects the light-emitting unit. In some embodiments ofthe method of manufacturing, the organic film contacts neither thedisplay units nor the encapsulation layer.

Each of the organic film and the planarization film may include any oneof polyimide and acryl. In some embodiments, the barrier layer may be aninorganic film. In some embodiments, the base substrate may be formed ofpolyimide. The method may further include, before the forming of thebarrier layer on one surface of the base substrate formed of polyimide,attaching a carrier substrate formed of a glass material to anothersurface of the base substrate, and before the cutting along theinterface portion, separating the carrier substrate from the basesubstrate. In some embodiments, the OLED display is a flexible display.

In some embodiments, the passivation layer is an organic film disposedon the TFT layer to cover the TFT layer. In some embodiments, theplanarization film is an organic film formed on the passivation layer.In some embodiments, the planarization film is formed of polyimide oracryl, like the organic film formed on the edge portion of the barrierlayer. In some embodiments, the planarization film and the organic filmare simultaneously formed when the OLED display is manufactured. In someembodiments, the organic film may be formed on the edge portion of thebarrier layer such that a portion of the organic film directly contactsthe base substrate and a remaining portion of the organic film contactsthe barrier layer while surrounding the edge portion of the barrierlayer.

In some embodiments, the light-emitting layer includes a pixelelectrode, a counter electrode, and an organic light-emitting layerdisposed between the pixel electrode and the counter electrode. In someembodiments, the pixel electrode is connected to the source/drainelectrode of the TFT layer.

In some embodiments, when a voltage is applied to the pixel electrodethrough the TFT layer, an appropriate voltage is formed between thepixel electrode and the counter electrode, and thus the organiclight-emitting layer emits light, thereby forming an image. Hereinafter,an image forming unit including the TFT layer and the light-emittingunit is referred to as a display unit.

In some embodiments, the encapsulation layer that covers the displayunit and prevents penetration of external moisture may be formed to havea thin film encapsulation structure in which an organic film and aninorganic film are alternately stacked. In some embodiments, theencapsulation layer has a thin film encapsulation structure in which aplurality of thin films are stacked. In some embodiments, the organicfilm applied to the interface portion is spaced apart from each of theplurality of display units. In some embodiments, the organic film isformed such that a portion of the organic film directly contacts thebase substrate and a remaining portion of the organic film contacts thebarrier layer while surrounding an edge portion of the barrier layer.

In one embodiment, the OLED display is flexible and uses the soft basesubstrate formed of polyimide. In some embodiments, the base substrateis formed on a carrier substrate formed of a glass material, and thenthe carrier substrate is separated.

In some embodiments, the barrier layer is formed on a surface of thebase substrate opposite to the carrier substrate. In one embodiment, thebarrier layer is patterned according to a size of each of the cellpanels. For example, while the base substrate is formed over the entiresurface of a mother panel, the barrier layer is formed according to asize of each of the cell panels, and thus a groove is formed at aninterface portion between the barrier layers of the cell panels. Each ofthe cell panels can be cut along the groove.

In some embodiments, the method of manufacture further comprises cuttingalong the interface portion, wherein a groove is formed in the barrierlayer, wherein at least a portion of the organic film is formed in thegroove, and wherein the groove does not penetrate into the basesubstrate. In some embodiments, the TFT layer of each of the cell panelsis formed, and the passivation layer which is an inorganic film and theplanarization film which is an organic film are disposed on the TFTlayer to cover the TFT layer. At the same time as the planarization filmformed of, for example, polyimide or acryl is formed, the groove at theinterface portion is covered with the organic film formed of, forexample, polyimide or acryl. This is to prevent cracks from occurring byallowing the organic film to absorb an impact generated when each of thecell panels is cut along the groove at the interface portion. That is,if the entire barrier layer is entirely exposed without the organicfilm, an impact generated when each of the cell panels is cut along thegroove at the interface portion is transferred to the barrier layer,thereby increasing the risk of cracks. However, in one embodiment, sincethe groove at the interface portion between the barrier layers iscovered with the organic film and the organic film absorbs an impactthat would otherwise be transferred to the barrier layer, each of thecell panels may be softly cut and cracks may be prevented from occurringin the barrier layer. In one embodiment, the organic film covering thegroove at the interface portion and the planarization film are spacedapart from each other. For example, if the organic film and theplanarization film are connected to each other as one layer, sinceexternal moisture may penetrate into the display unit through theplanarization film and a portion where the organic film remains, theorganic film and the planarization film are spaced apart from each othersuch that the organic film is spaced apart from the display unit.

In some embodiments, the display unit is formed by forming thelight-emitting unit, and the encapsulation layer is disposed on thedisplay unit to cover the display unit. As such, once the mother panelis completely manufactured, the carrier substrate that supports the basesubstrate is separated from the base substrate. In some embodiments,when a laser beam is emitted toward the carrier substrate, the carriersubstrate is separated from the base substrate due to a difference in athermal expansion coefficient between the carrier substrate and the basesubstrate.

In some embodiments, the mother panel is cut in units of the cellpanels. In some embodiments, the mother panel is cut along an interfaceportion between the cell panels by using a cutter. In some embodiments,since the groove at the interface portion along which the mother panelis cut is covered with the organic film, the organic film absorbs animpact during the cutting. In some embodiments, cracks may be preventedfrom occurring in the barrier layer during the cutting.

In some embodiments, the methods reduce a defect rate of a product andstabilize its quality.

Another aspect is an OLED display including: a barrier layer that isformed on a base substrate; a display unit that is formed on the barrierlayer; an encapsulation layer that is formed on the display unit; and anorganic film that is applied to an edge portion of the barrier layer.

EXAMPLES

An embodiment of the present disclosure provides the preparation ofcompounds of formula (I), (II), (III), or (IV) according to theprocedures of the following example(s), using appropriate materials.Those skilled in the art will understand that known variations of theconditions and processes of the following preparative procedures can beused to prepare these compounds. Moreover, by utilizing the proceduresdescribed in detail, one of ordinary skill in the art can prepareadditional compounds of the present disclosure.

General Information on Analytical Methods

The features of the invention will be described more specifically withreference to examples below. The materials, processes, procedures andthe like shown below may be appropriately modified unless they deviatefrom the substance of the invention. Accordingly, the scope of theinvention is not construed as being limited to the specific examplesshown below. The characteristics of samples were evaluated by using NMR(Nuclear Magnetic Resonance 500 MHz, produced by Bruker), LC/MS (LiquidChromatography Mass Spectrometry, produced by Waters), AC3 (produced byRIKEN KEIKI), High-performance UV/Vis/NIR Spectrophotometer (Lambda 950,produced by PerkinElmer, Co., Ltd.), Fluorescence Spectrophotometer(FluoroMax-4, produced by Horiba, Ltd.), Photonic multichannel analyzer(PMA-12 C10027-01, produced by Hamamatsu Photonics K.K.), Absolute PLQuantum Yield Measurement System (C11347, produced by HamamatsuPhotonics K.K.), Automatic Current voltage brightness measurement system(ETS-170, produced by System engineers co ltd), Life Time MeasurementSystem (EAS-26C, produced by System engineers co ltd), and Streak Camera(Model C4334, produced by Hamamatsu Photonics K.K.).

Example 1

The principle of the features may be described as follows for an organicelectroluminescent device as an example.

In an organic electroluminescent device, carriers are injected from ananode and a cathode to a light-emitting material to form an excitedstate for the light-emitting material, with which light is emitted. Inthe case of a carrier injection type organic electroluminescent device,in general, excitons that are excited to the excited singlet state are25% of the total excitons generated, and the remaining 75% thereof areexcited to the excited triplet state. Accordingly, the use ofphosphorescence, which is light emission from the excited triplet state,provides a high energy utilization. However, the excited triplet statehas a long lifetime and thus causes saturation of the excited state anddeactivation of energy through mutual action with the excitons in theexcited triplet state, and therefore the quantum yield ofphosphorescence may generally be often not high. A delayed fluorescentmaterial emits fluorescent light through the mechanism that the energyof excitons transits to the excited triplet state through intersystemcrossing or the like, and then transits to the excited singlet statethrough reverse intersystem crossing due to triplet-triplet annihilationor absorption of thermal energy, thereby emitting fluorescent light. Itis considered that among the materials, a thermal activation typedelayed fluorescent material emitting light through absorption ofthermal energy is particularly useful for an organic electroluminescentdevice. In the case where a delayed fluorescent material is used in anorganic electroluminescent device, the excitons in the excited singletstate normally emit fluorescent light. On the other hand, the excitonsin the excited triplet state emit fluorescent light through intersystemcrossing to the excited singlet state by absorbing the heat generated bythe device. At this time, the light emitted through reverse intersystemcrossing from the excited triplet state to the excited singlet state hasthe same wavelength as fluorescent light since it is light emission fromthe excited singlet state, but has a longer lifetime (light emissionlifetime) than the normal fluorescent light and phosphorescent light,and thus the light is observed as fluorescent light that is delayed fromthe normal fluorescent light and phosphorescent light. The light may bedefined as delayed fluorescent light. The use of the thermal activationtype exciton transition mechanism may raise the proportion of thecompound in the excited singlet state, which is generally formed in aproportion only of 25%, to 25% or more through the absorption of thethermal energy after the carrier injection. A compound that emits strongfluorescent light and delayed fluorescent light at a low temperature oflower than 100° C. undergoes the intersystem crossing from the excitedtriplet state to the excited singlet state sufficiently with the heat ofthe device, thereby emitting delayed fluorescent light, and thus the useof the compound may drastically enhance the light emission efficiency.

Example 2

The compounds of the invention can be synthesized by any method known toone of ordinary skills in the art. The compounds are synthesized fromthe commonly available starting material. The various moieties can beassembled via linear or branched synthetic routes.

Compounds 1 and 2

Compound 1

A mixture of K₂CO₃ (0.679 g, 4.91 mmol) and 91H-Carbazole (0.657 g, 3.93mmol) in NMP (15 mL) was stirred at r.t. for 1 h and then compound a(0.40 g, 0.655 mmol) was added. The mixture was stirred at 180° C. for18 h and then 195° C. for 11 h. The reaction mixture was quenched withH2O. The precipitated products was filtered, washed with MeOH, andpurified by silica gel column chromatography (hexane:toluene=1:1) togive compound 1 (0.507 g, 0.422 mmol) in 64% yield as white powder.1H-NMR (500 MHz, CDCl3, δ): 7.68 (d, J=8.0 Hz, 2H), 7.55 (d, J=8.0 Hz,211), 7.48 (d, J=8.0 Hz, 4H), 7.42-7.35 (m, 8H), 7.22-7.19 (m, 6H),7.06-6.99 (m, 12H), 6.93-6.85 (m, 8H), 6.81-6.71 (m, 12H).

MS (ASAP): 1199.9 (M+). Calcd for C86H54N8: 1199.4.

Compound 2

A mixture of K₂CO₃ (0.679 g, 4.91 mmol) and 3,6-Dimethylcarbazole (0.767g, 3.93 mmol) in NMP (15 mL) was stirred at r.t. for 1 h and thencompound a (0.40 g, 0.655 mmol) was added. The mixture was stirred at180° C. for 18 h and then 195° C. for 11 h. The reaction mixture wasquenched with H₂O. The precipitated products was filtered, washed withMeOH, and purified by silica gel column chromatography(hexane:toluene=1:1) to give compound 2 (0.664 g, 0.506 mmol) in 77%yield as white powder. 1H-NMR (500 MHz, CDCl3, δ): 7.41 (s, 2H), 7.36(d, J=8.0 Hz, 2H), 7.25-7.16 (m, 18H), 7.04 (t, J=8.0 Hz, 8H), 6.99-6.95(m, 4H), 6.74-6.68 (m, 12H), 2.38 (s, 6H), 2.24 (s, 12H), 2.20 (s, 6H).

MS (ASAP): 1311.1 (M+). Calcd for C94H70N8: 1310.6.

Compound 3

A mixture of K₂CO₃ (0.744 g, 5.38 mmol) and 3,6-Dimethylcarbazole (0.698g, 3.59 mmol) in NMP (15 mL) was stirred at r.t. for 1 h and thencompound b (0.6 g, 0.897 mmol) was added. The mixture was stirred at180° C. for 65 h and then 195° C. for 10 h. The reaction mixture wasquenched with H2O. The precipitated products was filtered, washed withMeOH, and purified by silica gel column chromatography (toluene) to givecompound 3 (0.386 g, 0.323 mmol) in 36% yield as white powder.

1H-NMR (500 MHz, CDCl3, δ): 7.46-7.42 (m, 4H), 7.39-7.35 (m, 4H),7.25-7.14 (m, 11H), 7.08-6.90 (m, 17H), 6.77 (d, J=7.5 Hz, 6H), 6.60 (t,J=7.5 Hz, 1H), 6.53 (t, J=7.5 Hz, 2H), 2.37-2.34 (m, 18H).

MS (ASAP): 1193.9 (M+). Calcd for C86H63N7: 1193.5.

Compound 4

A mixture of K₂CO₃ (0.79 g, 5.75 mmol) and 9H-Carbazole (0.64 g, 3.83mmol) in NMP (10 mL) was stirred at r.t. for 1 h and then compound c(0.35 g, 0.76 mmol) was added. The mixture was stirred at 160° C. for 20h. The reaction mixture was quenched with H2O. The precipitated productswas filtered, washed with MeOH to give compound 4 (0.52 g, 0.50 mmol) in65% yield as white powder. 1H-NMR (500 MHz, CDCl3, δ): 7.57-7.55 (m,2H), 7.53-7.51 (m, 2H), 7.48-7.46 (m, 2H), 7.34-7.21 (m, 13H), 7.17 (t,J=7.5 Hz, 4H), 7.11 (d, J=7.5 Hz, 2H), 6.99 (dd, J=7.5, 1.0 Hz, 2H),6.95-6.88 (m, 12H), 6.78-6.68 (m, 7H), 6.66 (dt, J=7.5, 1.0 Hz, 2H),6.59 (dt, J=7.5, 1.0 Hz, 2H).

MS (ASAP): 1044.4 (M+). Calcd for C76H48N6: 1044.4.

Compound 5

A mixture of K₂CO₃ (1.02 g, 7.38 mmol) and 9H-Carbazole (0.82 g, 4.90mmol) in NMP (30 mL) was stirred at r.t. for 1 h and compound A (0.375 g(0.622 mmol) was then added. The mixture was stirred at 190° C. for 37h. The reaction mixture was quenched with H2O. The precipitated productswas filtered, washed with MeOH and dried to give compound 2 (0.512 g(0.426 mmol, 7% yield) as white powder. MS (ASAP): 1198.4 (M+). Calcdfor C86H54N8: 1198.4.

Example 3 Preparation of Neat Films

In this example, the compound 1 synthesised in Example 2 wasvapor-deposited on a quartz substrate by a vacuum vapor depositionmethod under a condition of a vacuum degree of 10⁻³ Pa or less, so as toform a thin film having a thickness of 70 nm.

Preparation of Doped Films

The compound 1 and host were also vapor-deposited from a separate vapordeposition source on a quartz substrate by vacuum vapor depositionmethod under a condition of a vacuum degree of 10⁻³ Pa or less, so as toform a thin film having a thickness of 100 nm and a concentration of thecompound 1 of 20% by weight.

Evaluation of the Optical Properties

The samples were irradiated with light having a wavelength of 300 nm at300 K, and thus the light emission spectrum was measured and designatedas fluorescence. The spectrum at 77K was also measured and designated asphosphorescence. The lowest singlet energy (S1) and the lowest tripletenergy (Ti) was estimated from the onset of fluorescence andphosphorescence spectrum respectively. ΔEST was calculated from theenergy gap between S1 and T1. PLQY was also measured by excitation light300 nm. The time resolved spectrum was obtained by excitation light 337nm with Streak Camera, and the component with a short light emissionlifetime was designated as fluorescent light, whereas the component witha long light emission lifetime was designated as delayed fluorescentlight. The lifetimes of the fluorescent light component (τ_(prompt)) andthe delayed fluorescent light component (τ_(delay)) were calculated fromthe decay curves.

Preparation and Measurement of OLEDs

Thin films were laminated on a glass substrate having formed thereon ananode formed of indium tin oxide (ITO) having a thickness of 50 nm, by avacuum vapor deposition method at a vacuum degree of 1.0×10⁻⁴ Pa orless. Firstly, HAT-CN was formed to a thickness of 60 nm on ITO, andthereon TrisPCz was formed to a thickness of 30 nm. mCBP was formed to athickness of 5 nm, and thereon compound 1 and host were thenvapor-co-deposited from separate vapor deposition sources to form alayer having a thickness of 30 nm, which was designated as alight-emitting layer. At this time, the concentration of compound 1 was20% by weight. SF3-TRZ was then formed to a thickness of 5 nm, andthereon SF3-TRZ and Liq were vapor-co-deposited to a thickness of 30 nm.Liq was then vacuum vapor-deposited to a thickness of 2 nm, and thenaluminum (Al) was vapor-deposited to a thickness of 100 nm to form acathode, thereby producing organic electroluminescent devices andmeasured its photoelectrical properties.

The results of the same evaluation with compounds 2-4 and synthesized inExamples 2, instead of the compound 1 are also measured.

neat film or dope film PLQY compound concentration Lem (PL) ( in N2)ΔEst 1 100 wt % — 452 nm (neat) 10% (neat) 0.53 eV 2 100 wt % — 424 nm(neat)  6% (neat) 0.26 eV 3 100 wt % — 451 nm (neat)  4% (neat) 0.24 eV4 100 wt % — 448 nm (neat)  7% (neat) 0.35 eV Lifetime of neat film ordope film delayed PLQY flourescence compound concentration host Lem (PL)(in N2) τd ΔEst 1 20 wt % mCBP 456 nm 27.5% 2.57 us 2 20 wt % DPEPO 467nm 48.5% 3.68 us 3 20 wt % DPEPO 462 nm 28.2% 14.0 us 4 20 wt % PYD2Cznm  7.2% us device property@1000 nit structure concentration dopant J(mA/cm²) EQE *1 20 wt % 4CzIPN-tBu 1.51 17.1 *2 20 wt % 4CzIPN-tBu 1.4717.0 *1 20 wt % 4CzIPN-tBu 1.56 16.4 *2 20 wt % 4CzIPN-tBu 1.48 16.7 *1device structure ITO(100)/HATCN (10)/TrisPCz (25)/mCBP (5y EML [comp ×dopant = 80:20 ](30)/SF3-TRZ (10)/SF3-TRZ/Liq = 70:30 (35)/Liq (20 )/Al(100) *2 device structure ITO(100)/HATCN (10)/TrisPCz (25)/mCBP (5y EML[comp × dopant = 80:20 ](30)/comp × (10)/SF3-TRZ/Liq = 70:30 (35)/Liq(20 )/Al (100) *3 device structure ITO(100)/HATCN (10)/TrisPCz (25)/mCBP(5y EML [host comp × = 80:20 ](30)/SF3-TRZ (10)/SF3-TRZ/Liq = 70:30(35)/Liq (20 )/Al (100)

We claim:
 1. A compound of Formula (I):

wherein A is independently selected from

X^(A) is independently selected from O, S, and NR^(A′); R^(A) isindependently selected from hydrogen, deuterium, halogen, cyano,substituted or unsubstituted alkyl, substituted or unsubstituted alkoxy,substituted or unsubstituted aryl, substituted or unsubstituted aryloxy,substituted or unsubstituted heteroaryl, substituted or unsubstitutedheteroaryloxy, and silyl; two or more instances of R^(A) taken togethercan form a ring system; R^(A′) is independently selected from hydrogen,deuterium, substituted or unsubstituted alkyl, substituted orunsubstituted aryl, and substituted or unsubstituted heteroaryl; two ormore instances of R^(A′) and R^(A) taken together can form a ringsystem; D is independently selected from

X^(D) is independently selected from a bond, O, S, NR^(D′), C(O),substituted or unsubstituted methylene, substituted or unsubstitutedethylene, substituted or unsubstituted vinylene, substituted orunsubstituted o-arylene, and substituted or unsubstitutedo-heteroarylene; wherein each instance of methylene, ethylene, vinylene,o-arylene or o-heteroarylene can be substituted with one or moresubstituents independently selected from deuterium, substituted orunsubstituted alkyl, substituted or unsubstituted aryl, and substitutedor unsubstituted heteroaryl; two or more instances of X^(D) takentogether can form a ring system; R^(D) is independently selected fromhydrogen, deuterium, substituted or unsubstituted alkyl, substituted orunsubstituted alkoxy, substituted or unsubstituted amino, substituted orunsubstituted aryl, substituted or unsubstituted aryloxy, substituted orunsubstituted heteroaryl, substituted or unsubstituted heteroaryloxy,and silyl; two or more instances of R^(D) taken together can form a ringsystem; R^(D′) is independently selected from hydrogen, deuterium,substituted or unsubstituted alkyl, substituted or unsubstituted amino,substituted or unsubstituted aryl, and substituted or unsubstitutedheteroaryl; two or more instances of R^(D′) and R^(D) taken together canform a ring system; L^(A) and L^(D) are independently selected fromsingle bond, and substituted or unsubstituted arylene; wherein eachinstance of arylene can be substituted with one or more substituentsindependently selected from deuterium, substituted or unsubstitutedalkyl, and substituted or unsubstituted aryl; two or more of thesesubstituents taken together can form a ring system; Ar is independentlyselected from substituted or unsubstituted aryl and substituted orunsubstituted heteroaryl group, wherein the substituted or unsubstitutedheteroaryl group does not contain a ring nitrogen atom; each substituentis independently selected from deuterium, substituted or unsubstitutedalkyl, and substituted or unsubstituted aryl; two or more of thesesubstituents taken together can form a ring system; k is 2; n is 1 to 4;m is 0 to 3 (k+m+n) is 4 to 6; the two instances of A have a metarelationship or a para relationship; and each “*” represents a point ofattachment to Formula (I); provided that if n is greater than or equalto 2, then L^(A) is not a single bond; and if the two instances of Ahave a meta relationship, then n is greater than or equal to
 2. 2. Thecompound of claim 1, wherein D is


3. The compound of claim 1, wherein D is


4. The compound of claim 1, wherein D is


5. The compound of claim 1, wherein L^(D) is single bond.
 6. Thecompound of claim 1, wherein A is


7. The compound of claim 1, wherein L^(A) is a single bond.
 8. Thecompound of claim 1, wherein (k+m+n)=6.
 9. The compound of claim 1,wherein m is greater than or equal to 1 and less than or equal to
 3. 10.The compound of claim 1, wherein the compound of Formula (I) isrepresented by Formula (Ia):


11. The compound selected from the group consisting of:


12. The compound of claim 1, wherein the compound of Formula (I) isrepresented by Formula (Ib):


13. The compound of claim 1, wherein the two instances of A have a metarelationship, and at least one of the ortho positions to A is bondedwith D.
 14. An organic light-emitting diode (OLED) comprising an anode,a cathode, and at least one organic layer comprising a light emittinglayer between the anode and the cathode, wherein the light emittinglayer comprises: a host material; and a compound of Formula (I′);wherein the compound of Formula (I′) is a light emitting material

wherein: A is independently selected from

X^(A) is independently selected from O, S, and NR^(A′); R^(A) isindependently selected from hydrogen, deuterium, halogen, cyano,substituted or unsubstituted alkyl, substituted or unsubstituted alkoxy,substituted or unsubstituted aryl, substituted or unsubstituted aryloxy,substituted or unsubstituted heteroaryl, substituted or unsubstitutedheteroaryloxy, and silyl; two or more instances of R^(A) taken togethercan form a ring system; R^(A′) is independently selected from hydrogen,deuterium, substituted or unsubstituted alkyl, substituted orunsubstituted aryl, and substituted or unsubstituted heteroaryl; two ormore instances of R^(A′) and R^(A) taken together can form a ringsystem; D is independently selected from

X^(D) is independently selected from a bond, O, S, NR^(D′), C(O),substituted or unsubstituted methylene, substituted or unsubstitutedethylene, substituted or unsubstituted vinylene, substituted orunsubstituted o-arylene, and substituted or unsubstitutedo-heteroarylene; wherein each instance of methylene, ethylene, vinylene,o-arylene or o-heteroarylene can be substituted with one or moresubstituents independently selected from deuterium, substituted orunsubstituted alkyl, substituted or unsubstituted aryl, and substitutedor unsubstituted heteroaryl; two or more instances of X^(D) takentogether can form a ring system; R^(D) is independently selected fromhydrogen, deuterium, substituted or unsubstituted alkyl, substituted orunsubstituted alkoxy, substituted or unsubstituted amino, substituted orunsubstituted aryl, substituted or unsubstituted aryloxy, substituted orunsubstituted heteroaryl, substituted or unsubstituted heteroaryloxy,and silyl; two or more instances of R^(D) taken together can form a ringsystem; R^(D′) is independently selected from hydrogen, deuterium,substituted or unsubstituted alkyl, substituted or unsubstituted amino,substituted or unsubstituted aryl, and substituted or unsubstitutedheteroaryl; two or more instances of R^(D′) and R^(D) taken together canform a ring system; L^(A) and L^(D) are independently selected fromsingle bond, and substituted or unsubstituted arylene; wherein eachinstance of arylene can be substituted with one or more substituentsindependently selected from deuterium, substituted or unsubstitutedalkyl, and substituted or unsubstituted aryl; two or more of thesesubstituents taken together can form a ring system; Ar is independentlyselected from substituted or unsubstituted aryl and substituted orunsubstituted heteroaryl group, wherein the substituted or unsubstitutedheteroaryl group does not contain a ring nitrogen atom; each substituentis independently selected from deuterium, substituted or unsubstitutedalkyl, and substituted or unsubstituted aryl; two or more of thesesubstituents taken together can form a ring system; k is 2; n is 1 to 4;m is 0 to 3 (k+m+n) is 3 to 6; the two instances of A have a metarelationship or a para relationship; and each “*” represents a point ofattachment to Formula (I); provided that if n is greater than or equalto 2, then L^(A) is not a single bond; and if the two instances of Ahave a meta relationship, then n is greater than or equal to
 2. 15. Ascreen or a display comprising a compound of claim 1.